最新第十四章习题答案final

合集下载

八年级数学上册《第十四章公式法》练习题附答案-人教版

八年级数学上册《第十四章公式法》练习题附答案-人教版一、选择题1.下列各式中，能用平方差公式因式分解的是( )A.x2+4y2B.x2﹣2y2+1C.﹣x2+4y2D.﹣x2﹣4y22.计算：852﹣152=( )A.70B.700C.4900D.70003.因式分解的结果是(2x－y)(2x＋y)的是 ( )A.－4x2＋y2B.4x2＋y2C.－4x2－y2D.4x2－y24.已知x2-y2=6，x-y=1，则x+y等于( )A.2B.3C.4D.65.下列因式分解正确的是( )A.6x＋9y＋3＝3(2x＋3y)B.x2＋2x＋1＝(x＋1)2C.x2﹣2xy﹣y2＝(x﹣y)2D.x2＋4＝(x＋2)26.下列各式中不能用完全平方公式因式分解的是( )A.-x2+2xy-y2B.x4-2x3y+x2y2C.(x2-3)2-2(3-x2)+1D.x2-xy+12y27.若多项式x2+mx+4能用完全平方公式分解因式，则m的值可以是( )A.4B.﹣4C.±2D.±48.若a+b=3,a-b=7,则b2-a2的值为( )A.-21B.21C.-10D.109.小明在抄因式分解的题目时，不小心漏抄了x的指数，他只知道该数为不大于10的正整数，并且能利用平方差公式因式分解，他抄在作业本上的式子是x□﹣4y2(“□”表示漏抄的指数)，则这个指数可能的结果共有( )A.2种B.3种C.4种D.5种10.如果一个正整数可以表示为两个连续奇数的平方差，那么称该正整数为“和谐数”如(8=32﹣12，16=52﹣32，即8，16均为“和谐数”)，在不超过2017的正整数中，所有的“和谐数”之和为( )A.255054B.255064C.250554D.255024二、填空题11.因式分解：m2﹣4= .12.因式分解：(2a+b)2﹣(a+2b)2= .13.计算：2 019×2 021-2 0202=__________.14填空根据题意填空：x2﹣6x+(______)=(x﹣______)215.已知x＋y＝0.2，x＋3y＝1，则代数式x2＋4xy＋4y2的值为________.16.观察下列各式：(1)42－12=3×5；(2)52－22=3×7；(3)62－32=3×9；………则第n(n是正整数)个等式为_____________________________.三、解答题17.因式分解：5x2+10x+518.因式分解：x2(x﹣y)+(y﹣x)19.因式分解：2a3-12a2＋18a20.因式分解：9a2(x﹣y)+4b2(y﹣x)21.在一块边长为a cm的正方形纸板中，四个角分别剪去一个边长为b cm的小正方形，利用因式分解计算：当a＝98 cm，b＝27 cm时，剩余部分的面积是多少？22.已知x－y=2，y－z=2，x＋z=4，求x2－z2的值.23.已知x2+y2﹣4x+6y+13=0，求x2﹣6xy+9y2的值.24.两位数相乘：19×11=209,18×12=216,25×25=625,34×36=1 224，47×43=2 021，…(1)认真观察，分析上述各式中两因数的个位数字、十位数字分别有什么联系，找出因数与积之间的规律，并用字母表示出来；(2)验证你得到的规律.25.中国古贤常说万物皆自然，而古希腊学者说万物皆数.同学们还记得我们最初接触的数就是“自然数”吧!在数的学习过程中，我们会对其中一些具有某种特性的自然数进行研究，我们研究了奇数、偶数、质数、合数等.现在我们来研究另一种特珠的自然数—“n喜数”.定义：对于一个两位自然数，如果它的个位和十位上的数字均不为零，且它正好等于其个位和十位上的数字的和的n倍(n为正整数)，我们就说这个自然数是一个“n喜数”.例如：24就是一个“4喜数”，因为24=4×(2+4)；25就不是一个“n喜数”因为25≠n(2+5).(1)判断44和72是否是“n喜数”？请说明理由；(2)试讨论是否存在“7喜数”若存在请写出来，若不存在请说明理由.参考答案1.C2.D3.D4.D5.B.6.D7.D8.A9.D10.D11.答案为：(m+2)(m﹣2).12.答案为：3(a+b)(a﹣b).13.答案为：-114.答案为：9，3；15.答案为：0.36.16.答案为：(n+3)2-n2=3(2n+3)17.解：原式=5(x2+2x+1)=5(x+1)2；18.解：原式=x2(x﹣y)+(y﹣x)=(x﹣y)(x2﹣1)=(x﹣y)(x+1)(x﹣1)；19.解：原式=2a(a-3)220.解：原式=(x﹣y)(3a+2b)•(3a﹣2b).21.解：根据题意，得剩余部分的面积是：a2－4b2＝(a＋2b)(a－2b)＝152×44＝6 688(cm2). 22.解：由x－y=2，y－z=2，得x－z=4.又∵x＋z=4∴原式=(x＋z)(x－z)=16.23.解：∵x2+y2﹣4x+6y+13=(x﹣2)2+(y+3)2=0∴x﹣2=0，y+3=0，即x=2，y=﹣3则原式=(x﹣3y)2=112=121.24.解：(1)上述等式的规律是：两因数的十位数字相等，个位数字相加等于10而积后两位是两因数个位数字相乘、前两位是十位数字相乘，乘积再加上这个十位数字之和；如果用m表示十位数字，n表示个位数字的话则第一个因数为10m＋n，第二个因数为10m＋(10－n)，积为100m(m＋1)＋n(10－n)；表示出来为：(10m＋n)[10m＋(10－n)]=100m(m＋1)＋n(10－n)；(2)∵左边=(10m＋n)(10m－n＋10)=(10m＋n)[10(m＋1)－n]=100m(m＋1)－10mn＋10n(m＋1)－n2=100m(m＋1)－10mn＋10mn＋10n－n2=100m(m＋1)＋n(10－n)=右边∴(10m＋n)[10m＋(10－n)]=100m(m＋1)＋n(10－n)，成立.25.解：(1)44不是一个“n喜数”，因为44≠n(4+4)72是一个“8喜数”，因为72=8(2+7)；(2)设存在“7喜数”，设其个位数字为a十位数字为b，(a，b为1到9的自然数)由定义可知：10b+a=7(a+b)化简得：b=2a因为a，b为1到9的自然数∴a=1，b=2；a=2，b=4；a=3，b=6；a=4，b=8；∴“7喜数”有4个：21、42、63、84.。

C++Primer 第14章-重载操作符与转换-课后习题答案

第十四章重载操作符与转换1。

在什么情况下重载操作符与内置操作符不同？在什么情况下重载操作符与内置操作符相同？重载操作符必须具有至少一个类类型或枚举类型的操作数。

重载操作符不保证操作数的求值顺序，例如对&& 和|| 的重载版本不再具有“短路求值”的特性，两个操作数都要进行求值，而且不规定操作数的求值顺序。

对于优先级和结合性及操作数的数目都不变。

2。

为Sales_item编写输入、输出。

加以及复合赋值操作符的重载声明。

class Sales_item{friend std::istream& operator >> ( std::istream&, Sales_item& );friend std::ostream& operator <<(std::ostream&, const Sales_item&);public:Sales_item& operator += ( const Sales_item& );};Sales_item operator+ ( const Sales_item&, const Sales_item& )3。

解释如下程序，假定Sales_item构造函数的参数是一个string,且不为explicit.解释如果构造函数为explicit会怎样。

string null_book = “0-000-00000-0”;Sales_item item(cin);item += null_book;第一句：调用接受一个C风格的字符串形参的string构造函数，创建一个string临时对象，然后使用string复制构造函数用这个临时对象初始化string对象null_book,第二句：从标准输入设备读入数据，创建Sales_item对象item。

第三句：首先调用接受一个string参数的Sales_item构造函数，创建一个临时对象，然后调用Sales_item的复合重载操作符+=，将这个Sales_item临时对象加到item对象上，如果构造函数为explicit，则不能进行从string对象到Sales_item对象的隐式转换，第三句将不能被编译。

C++ primer plus 14章—15章课后答案

14.4#ifndef WORKERMI_H_#define WORKERMI_H_#include<iostream>#include<string>#include<cstdlib>usingnamespace std;class person{private:stringfirstname;stringlastname;protected:virtualvoid data(){cout<<"firstname: "<<firstname<<endl;cout<<"lastname: "<<lastname<<endl;};virtualvoid get(){getline(cin,firstname);cout<<"enter person's lastname: ";getline(cin,lastname);cin.get();}public:person():firstname("no one"),lastname("no one"){}person(string & s1,string & s2):firstname(s1),lastname(s2){} person(person & s){firstname=s.firstname;lastname=stname;}virtual ~person()=0;virtualvoid set()=0;virtualvoid show() =0;};class gunslinger:virtualpublic person{private:double time;int nick;protected:void data(){cout<<"time: "<<time<<endl;cout<<"nick: "<<nick<<endl;}void get(){cout<<"enter time to draw the gun: ";cin>>time;cout<<"enter nick of the gun: ";cin>>nick;cin.get();}public:gunslinger():person(),time(0),nick(0){}gunslinger(string & s1 ,string s2,double t=0,int n=0):person(s1,s2),time(t),nick(n){} gunslinger( person &p,double t=0,int n=0):person(p),time(t),nick(n){}void set(){cout<<"enter gunslinger's firstname: ";person::get();get();}void show(){cout<<"category: gunslinger\n";person::data();data();}double draw(){return time;}};class pokerplayer : virtualpublic person{private:int value;protected:void data(){cout<<"playing card: "<<value<<endl;}void get(){value=rand()%52;}public:pokerplayer():person(),value(0){}pokerplayer(string & s1,string & s2,int v=0):person(s1,s2),value(v){} pokerplayer(person &p,int v=0):person(p),value(v){}void set(){cout<<"enter pokerplayer'sfirstname: ";person::get();get();}void show(){cout<<"category: pokerplayer\n";person::data();data();}int draw(){return value;}};class baddude: public gunslinger, public pokerplayer{protected:void data(){gunslinger::data();pokerplayer::data();}void get(){gunslinger::get();pokerplayer::get();}public:baddude(){}baddude(string & s1,string & s2,double t=0,int n=0,int v=0):person(s1,s2),gunslinger(s1,s2,t,n),pokerplayer(s1,s2,v){}baddude(person &p,double t=0,int n=0,int v=0):person(p),gunslinger(p,t,n),pokerplayer(p,v){}baddude(person &p,double t=0,int n=0):person(p),gunslinger(p,t,n),pokerplayer(p){} baddude(person &p,int v=0):person(p),gunslinger(p),pokerplayer(p,v){}void set(){cout<<"enter baddue'sfirstname: ";person::get();get();}void show(){cout<<"category: baddue\n";person::data();data();}};#endif#include<iostream>#include<cstring>#include"person.h"int main(){usingnamespace std;person * lolas[5];int ct;for(ct=0;ct<5;ct++){char choice;cout<<"enter the category:\n"<<"g: gunslinger p: pokerplayer "<<"b: baddude q: quit\n";cin>>choice;while(strchr("gpbq",choice)==NULL){cout<<"please enter a g,p,b, or q: ";cin>>choice;}if (choice=='q')break;switch(choice){case'g': lolas[ct]=new gunslinger;break;case'p': lolas[ct]=new pokerplayer;break;case'b': lolas[ct]=new baddude;break;}cin.get();lolas[ct]->set();}cout<<"\nhere is your staff:\n";for(int i=0;i<5;i++){cout<<endl;lolas[i]->show();}for(int i=0;i<5;i++)delete lolas[i];cout<<"bye.\n";return 0;}14.5emp.h#include<iostream>#include<string>usingnamespace std;class abstr_emp{private:string fname;string lname;string job;public:abstr_emp(){fname="no";lname="no";job="no";}abstr_emp(const string &fn,const string &ln,const string & j):fname(fn),lname(ln),job(j){}virtualvoid showall() const{cout<<"firstname: "<<fname<<endl;cout<<"lastname: "<<lname<<endl;cout<<"job: "<<job<<endl;}virtualvoid setall(){cout<<"enter first name: ";cin>>fname;cin.get();cout<<"enter last name: ";cin>>lname;cin.get();cout<<"enter job: ";getline(cin,job);}friend std::ostream&operator<<(ostream&os,const abstr_emp& e){os<<"firstname: "<<e.fname<<endl;os<<"lastname: "<<e.lname<<endl;return os;};virtual ~abstr_emp()=0{};};class employee: public abstr_emp{public:employee():abstr_emp(){}employee(const string &fn,const string &ln,const string & j):abstr_emp(fn,ln,j){} virtualvoid showall () const{abstr_emp::showall();}virtualvoid setall(){abstr_emp::setall();}};class manager: virtualpublic abstr_emp{private:int inchargeof;protected:int inchargeof1() const {return inchargeof;}int& inchargeof1(){return inchargeof;}public:manager():abstr_emp(),inchargeof(0){}manager(const string &fn,const string &ln,const string&j,int ico=0):abstr_emp(fn,ln,j),inchargeof(ico){}manager(const abstr_emp&e,int ico):abstr_emp(e),inchargeof(ico){} manager(const manager & m):abstr_emp(m){inchargeof=m.inchargeof;}virtualvoid showall() const{abstr_emp::showall();cout<<"inchargeof: "<<inchargeof<<endl;}virtualvoid setall(){abstr_emp::setall();cout<<"enter inchargeof: ";cin>>inchargeof;while(cin.get()!='\n')continue;}};class fink:virtualpublic abstr_emp{private:string reportsto;protected:const string reportsto1() const{return reportsto;}string & reportsto1(){return reportsto;public:fink():abstr_emp(),reportsto("none"){}fink(const string &fn,const string &ln,const string &j,const string&rpo):abstr_emp(fn,ln,j),reportsto(rpo){}fink(const abstr_emp&e,const string &rpo):abstr_emp(e),reportsto(rpo){}fink(const fink & e):abstr_emp(e){reportsto=e.reportsto;}virtualvoid showall() const{abstr_emp::showall();cout<<"reportsto: "<<reportsto<<endl;}virtualvoid setall(){abstr_emp::setall();cout<<"enter reportsto: ";cin>>reportsto;while(cin.get()!='\n')continue;}};class highfink:public manager,public fink{public:highfink(){}highfink(const string &fn,const string &ln,const string &j,const string&rpo,int ico):abstr_emp(fn,ln,j),fink(fn,ln,j,rpo),manager(fn,ln,j,ico){} highfink(const abstr_emp&e,const string&rpo,int ico):abstr_emp(e),manager(e,ico),fink(e,rpo){}highfink(const fink &f,int ico):abstr_emp(f),manager(f,ico){}highfink(const manager &m,const string &rpo):abstr_emp(m),manager(m),fink(m,rpo){} highfink(const highfink& h):abstr_emp(h),manager(h),fink(h){}virtualvoid showall() const{abstr_emp::showall();cout<<"inchargeof: "<<manager::inchargeof1()<<endl;cout<<" reportsto: "<<fink::reportsto1()<<endl;virtualvoid setall(){abstr_emp::setall();cout<<"enter inchargeof: ";cin>>manager::inchargeof1();while(cin.get()!='\n')continue;cout<<"enter reportsto: ";cin>>fink::reportsto1();while(cin.get()!='\n')continue;}};main.cpp#include<iostream>#include"emp.h"usingnamespace std;int main(){employee em("Trip","Harris","Thumper");cout<<em<<endl;em.showall();manager ma("Amorphia","Spindragon","Nuancer",5);cout<<ma<<endl;ma.showall();fink fi("Matt","Oggs","Oiler","Juno Barr");cout<<fi<<endl;fi.showall();highfinkhf(ma,"Curly Kew");hf.showall();cout<<"Press a key for next phase:\n";cin.get();highfink hf2;hf2.setall();cout<<"Using an abstr_emp * pointer: \n";abstr_emp * tri[4]={&em, &fi, &hf, &hf2};for(int i=0;i<4;i++)tri[i]->showall();cin.get();return 0;}15.1remote.h#include<iostream>usingnamespace std;class tv{friendclass remote;public:enum{off,on};enum{minval,maxval=20};enum{antenna,cable};enum{Tv,dvd};tv(int s=off,intmc=125):state(s),volume(5),maxchannel(mc),channel(2),mode(cable),input(Tv){} void onoff(){state=(state==on)?off:on;}bool ison()const{return state==on;}bool volup(){if(volume<maxval){volume++;returntrue;}elsereturnfalse;}bool voldown(){if(volume>minval){volume--;returntrue;}elsereturnfalse;}void chanup(){if(channel<maxchannel)channel++;elsechannel=1;}void chandown(){if(channel>1)channel--;elsechannel=20;}void set_mode(){mode=(mode==antenna)?cable:antenna;}void set_input(){input=(input=Tv)?dvd: Tv;}void settings()const{cout<<"tv is "<<(state==off?"off":"on")<<endl;if(state==on){cout<<"volume setting = "<<volume<<endl;cout<<"channel setting = "<<channel<<endl;cout<<"mode = "<<(mode == antenna?"antenna":"cable")<<endl;cout<<"input = "<<(input == Tv?"Tv":"dvd")<<endl;}}void set_condition(remote & r);private:int state;int volume;int maxchannel;int channel;int mode;int input;};class remote{friendclass tv;enum{default1,interact};private:int mode;int condition;public:remote(int m=tv::Tv,int c=default1):mode(m),condition(c){}bool volup(tv& t){return t.volup();}bool voldown(tv& t){return t.voldown();}void onoff(tv& t){t.onoff();}void chanup(tv& t){t.chanup();}void chandown(tv& t){t.chandown();}void set_chan(tv&t,int c){t.channel=c;}void set_mode(tv& t){t.set_mode();}void set_input(tv& t){t.set_input();}void show(){cout<<"remote condition: "<<condition<<endl;}void set_condition(){condition=(condition==default1)?interact:default1;} };inlinevoid tv:: set_condition(remote & r){if(tv::state==on)r.set_condition();}main.cpp#include<iostream>#include"remote.h"int main(){usingnamespace std;tv s42;cout<<"initial settings for 42\"Tv: \n";s42.settings();s42.onoff();s42.chanup();cout<<"\nadjusted settings for 42\"Tv: \n";s42.settings();remote grey;grey.set_chan(s42,10);grey.volup(s42);grey.volup(s42);cout<<"\n42\"settings after using remote: \n";s42.settings();grey.show();s42.set_condition(grey);cout<<"set condition using tv: "<<endl;grey.show();tv s58(tv::on);s58.set_mode();grey.set_chan(s58,28);cout<<"\n58\"settings: \n";s58.settings();cin.get();return 0;}15.2error.h#include<exception>#include<iostream>usingnamespace std;class bad_hmean:public exception{public:bad_hmean(){}constchar * what(){ return"bad arguments to hmean()";} };class bad_gmean:public exception{public:bad_gmean(){}constchar * what(){return"bad arguments to gmean()";} };main.cpp#include<iostream>#include"erroe.h"#include<cmath>double hmean(double a,double b);double gmean(double a,double b);int main(){usingnamespace std;double x,y,z;cout<<"enter two numbers: ";while(cin>>x>>y){try{z=hmean(x,y);cout<<"harmonic mean of "<<x<<" and "<<y<<" is "<<z<<endl;cout<<"geometric mean of "<<x<<" and "<<y<<" is "<<gmean(x,y)<<endl;cout<<"enter next set of numbers <q to quit>: ";}catch (bad_hmean&bg){cout<<bg.what()<<endl;cout<<"try again.\n";continue;}catch (bad_gmean& hg){cout<<hg.what()<<endl;cout<<"values used: "<<x<<", "<<y<<endl;cout<<"sorry,you don't get to play any more.\n";break;}}cout<<"bye!\n";cin.get();cin.get();return 0;}double hmean(double a,double b){if (a==-b)throw bad_hmean();return 2.0*a*b/(a+b);}double gmean(double a,double b){if(a<0||b<0)throw bad_gmean();return std::sqrt(a*b);}15.3erroe.h#include<exception>#include<iostream>usingnamespace std;class logic:public exception{private:double v1;double v2;public:logic(double a=0,double b=0):v1(a),v2(b){}virtualvoid show() const{cout<<"values used: "<<v1<<","<<v2<<endl;}};class bad_hmean:public logic{public:bad_hmean(double a=0,double b=0):logic(a,b){} void show() const{logic::show();cout<<"invalid argument: a= -b\n";}};class bad_gmean:public logic{public:bad_gmean(double a=0,double b=0):logic(a,b){}void show()const{logic::show();cout<<"gmean() arguments: "<<" should be >=0\n";}};main.cpp#include<iostream>#include"erroe.h"#include<cmath>double hmean(double a,double b);double gmean(double a,double b);int main(){usingnamespace std;double x,y,z;cout<<"enter two numbers: ";while(cin>>x>>y){try{z=hmean(x,y);cout<<"harmonic mean of "<<x<<" and "<<y<<" is "<<z<<endl;cout<<"geometric mean of "<<x<<" and "<<y<<" is "<<gmean(x,y)<<endl;cout<<"enter next set of numbers <q to quit>: ";}catch(logic & e){e.show();break;}/*catch (bad_hmean&bg){cout<<bg.what()<<endl;bg.mesg();cout<<"try again.\n";continue;}catch (bad_gmean& hg){cout<<hg.what();hg.mesg();cout<<"values used: "<<x<<", "<<y<<endl;cout<<"sorry,you don't get to play any more.\n";break;}*/}cout<<"bye!\n";cin.get();cin.get();return 0;}double hmean(double a,double b){if (a==-b)throw bad_hmean(a,b);return 2.0*a*b/(a+b);}double gmean(double a,double b){if(a<0||b<0)throw bad_gmean(a,b);return std::sqrt(a*b);}15.4sales.h#include<stdexcept>#include<string>usingnamespace std;class sales{public:enum {MONTHS=12};class bad_index:public logic_error{private:int bi;public:explicit bad_index(int ix,const string & s="index error in sales object\n");int bi_val() const{return bi;}virtual ~bad_index() throw() {}};explicit sales(int yy=0);sales(int yy,constdouble * gr, int n);virtual ~sales(){}int year1() const {return year;}virtualdoubleoperator[](int i)const;virtualdouble&operator[](int i);private:double gross[MONTHS];int year;};class labeledsales: public sales{private:string label;public:class nbad_index: public sales::bad_index{private:stringlbl;public:nbad_index(const string &lb,int ix,const string & s="Index error in labeledsales object\n");const string &label_val()const{return lbl;}virtual ~nbad_index() throw(){}};explicit labeledsales(const string &lb="none",int yy=0);labeledsales(const string &lb,int yy, constdouble * gr ,int n);virtual ~labeledsales(){}const string & label1() const {return label;}virtualdoubleoperator[](int i)const;virtualdouble&operator[](int i);};sales.cpp#include"sale.h"usingnamespace std;sales::bad_index::bad_index(int ix,const string & s):logic_error(s),bi(ix) {}sales::sales(int yy){year=yy;for(int i=0;i<MONTHS;++i)gross[i]=0;}sales::sales(int yy,constdouble * gr,int n){year=yy;int lim=(n<MONTHS)?n:MONTHS;int i;for(i=0;i<lim;++i)gross[i]=gr[i];for(;i<MONTHS;++i)gross[i]=0;}double sales::operator[](int i)const{if(i<0||i>=MONTHS)thrownew bad_index(i);return gross[i];}double& sales::operator[](int i){if(i<0||i>=MONTHS)thrownew bad_index(i);return gross[i];}labeledsales::nbad_index::nbad_index(const string &lb,int ix,const string & s):sales::bad_index(ix,s){lbl=lb;}labeledsales::labeledsales(const string &lb, int yy):sales(yy){label=lb;}labeledsales::labeledsales(const string &lb,int yy,constdouble * gr,int n):sales(yy,gr,n) {label=lb;}double labeledsales::operator[](int i)const{if(i<0||i>=MONTHS)thrownew nbad_index(label1(),i);return sales::operator[](i);}double&labeledsales::operator[](int i){if(i<0||i>=MONTHS)thrownew nbad_index(label1(),i);return sales::operator[](i);}main.cpp#include<iostream>#include"sale.h"int main(){usingnamespace std;double vals1[12]={1220,1100,1122,2212,1232,2334,2884,2393,3302,2922,3002,3544};double vals2[12]={12,11,22,21,32,34,28,29,33,29,32,35};sales sales1(2011,vals1,12);labeledsales sales2("blogstar",2012,vals2,12);cout<<"first try block:\n";labeledsales::nbad_index * ps;try{int i;cout<<"year = "<<sales1.year1()<<endl;for(i=0;i<12;++i){cout<<sales1[i]<<" ";if(i % 6==5)cout<<endl;}cout<<"year = "<<sales2.year1()<<endl;cout<<"label = "<<bel1()<<endl;for(i=0;i<=12;++i){cout<<sales2[i]<<" ";if(i % 6==5)cout<<endl;}cout<<"end of try block 1.\n";}catch(sales::bad_index * bad){cout<<bad->what();cout<<"bad index: "<<bad->bi_val()<<endl;if(ps=dynamic_cast<labeledsales::nbad_index * >(bad)) cout<<"company: "<<ps->label_val()<<endl;}labeledsales::nbad_index * ps1;try{sales2[2]=37.5;sales1[20]=23345;cout<<"end of try block 2.\n";}catch(sales::bad_index * bad){cout<<bad->what();cout<<"bad index: "<<bad->bi_val()<<endl;if(ps1=dynamic_cast<labeledsales::nbad_index * >(bad)) cout<<"company: "<<ps1->label_val()<<endl;}cout<<"done\n";cin.get();cin.get();return 0;}。

课后习题(Final)

课后习题(Final)Key Terms01.Autarky Autarky is the quality of being self-sufficient. Usually the term is applied to political states or their economic systems. Autarky exists whenever an entity can survive or continue its activities without external assistance or international trade. If a self-sufficient economy also refuses all trade with the outside world then it is called a closed economy.munity indifference curve A community indifference curve shows the various combinations of two commodities that yield equal satisfaction to the community or nation. Higher curves refer to greater satisfaction, lower curves to less satisfaction. Community indifference curves are negatively sloped and convex from the origin. To be useful, they must not cross.03.Deindustrialization Deindustrialization is a process of social and economic change caused by the removal or reduction of industrial capacity or activityin a country or region, especially heavy industry or manufacturing industry.It is the opposite of industrialization.04.Equilibrium-relative commodity price in isolation The equilibrium-relative commodity price in isolation is given by the slope of the common tangent to the nation’s production frontier and indifferent curve at the autarky point of production and consumption.Thus, the equilibrium-relative commodity price in isolation is PA=PX/PY=1/4 in Nation 1 and PA’ =PX/PY=4 in Nation 2.(see Figure 3.3) 05.Gains from exchange 06.Gains from specialization 5-6.A nation’s gains from trade can be broken down into comp onents: the gains from exchange and the gains from specialization. 07.Incomplete specialization Incomplete specialization means production of goods that compete with imports. In contrast, under increasing opportunity costs, there is incomplete specialization in production in both nations. 08.Increasing opportunity cost Increasing opportunity cost mean that the nation must give up more and more of one commodity to release just enough resources to produce each additional unit of another commodity. 09.Marginal rate of substitution (MRS) The MRS of X for Y in consumption refers to the amount of Y that a nation could give up for one extra unit of X and still remain on the same indifferent curve.MRS = (Absolute)Slop of community indifference curve 10.Marginal rate of transformation (MRT) MRT of X for Y refers to the amount of Y that a nation must give up toproduce each additional unit of X.Thus, MRT is another name for opportunity cost of X (the commodity measured along the horizonal axis) and is given by the (absolute) slope of the production frontier at the point of production.MRT（X for Y） = Opportunity cost of X =(Absolute)Slop of the production frontier11.Revealed comparative advantage The revealed comparative advantage is an index used in international economics for calculating the relative advantage or disadvantage of a certain country in a certain class of goods or services as evidenced by trade flows. It is based on the Ricardian comparative advantage concept.Question for Review1.In what way is the material in this chapter more realistic than that of Chapter 2？Chapter 3 extends our simple trade modle to the more realistic case of increasing opportunity cost .Taste or Demand preferences are introduced with commodity indifference curves2.How are the taste or demand preferences ,of a nation introduced in this chapter？Why are they needed？In a nation,the tastes or the demand preferences are given by community （or social）indifference curves. Because they differ on the assumption that tastes ,or demand preferences ,are different in the two nations3.Why does a production frontier that is concave from the origin indicate increasing opportunity costs in both commodities？what does the slope of the production frontier measure？How does the slope change as the nation produces more of the commodity measured along the horizontal axis？more of the commodity measured along the vertical axis？That’s always the case because as a nation consumes more of X ,it must consume less of Y if the nation is to have the same level of satisfaction. The slope of the production frontier is measured by the marginal rate of substitution(MRS) The more of X and the lessof Y a nation consumes, the more valuable to the nation is a unit of Y at the margin compared with a unit of X. The slope tends to be flater4.What is the reason for increasing opportunity costs？Why do the production frontiers of different nations have different shapes？The reason is that by the trading with each other, both nations end up consuming more than in the absence of trade.Because different nations incur increasing opportunity costs in the different productions.This is reflected in the increasing slope of their production frontier5.What does a community indifference curve measure？What are its characteristiics？What does the slope of an indifference curve measure？Why does it decline as the nation consumes more of the commodity measured along the horizontal axis？The community indifference curve is measured by income distributionand consumption pattern. The community indifference curves must not intersect,their slope is negative. The slope of community indifference curve are measured by the marginal rate of substitution,too.Declining MRS means that community indifference curves are convex from the origin.Thus, while increasing opportunity cost in production is reflected in concave production frontiers,a declining marginal rate of substitution in consumption isreflected in convex community indifference curves. 6.What difficulties arise in the use of community indifference curves in trade theory？How can these difficulties be overcome？The difficulties ---A particular set，or map,of community indifference curves refers to a particular income distribution within the nation.Adifferent income distribution would result in a completely new set of indifference curves,which may intersect precious indifference curves. The so �Ccalled compensation principle and restrictive assumption are used to overcome them but don’t c ompletely eliminate all the conceptual difficulties inherent in using community indifference curves7．What is meant by the equilibrium-relative commodity price inisolation? How is this price determined in each nation ? How does it define the natio n’s comparative advantage?The equilibrium-relative commodity price in isolation is given by the slope of the commom tangent to the nation’s production frontier and indifference curve at the autarky point of production and consumption.感谢您的阅读，祝您生活愉快。

Solution_国际财务管理_切奥尔尤恩_课后习题答案_第十四章

CHAPTER 14 INTEREST RATE AND CURRENCY SWAPSSUGGESTED ANSWERS AND SOLUTIONS TO END-OF-CHAPTERQUESTIONS AND PROBLEMSQUESTIONS1. Describe the difference between a swap broker and a swap dealer.Answer: A swap broker arranges a swap between two counterparties for a fee without taking a risk position in the swap. A swap dealer is a market maker of swaps and assumes a risk position in matching opposite sides of a swap and in assuring that each counterparty fulfills its contractual obligation to the other.2. What is the necessary condition for a fixed-for-floating interest rate swap to be possible?Answer: For a fixed-for-floating interest rate swap to be possible it is necessary for a quality spread differential to exist. In general, the default-risk premium of the fixed-rate debt will be larger than the default-risk premium of the floating-rate debt.3. Discuss the basic motivations for a counterparty to enter into a currency swap.Answer: One basic reason for a counterparty to enter into a currency swap is to exploit the comparative advantage of the other in obtaining debt financing at a lower interest rate than could be obtained on its own. A second basic reason is to lock in long-term exchange rates in the repayment of debt service obligations denominated in a foreign currency.4. How does the theory of comparative advantage relate to the currency swap market?Answer: Name recognition is extremely important in the international bond market. Without it, even a creditworthy corporation will find itself paying a higher interest rate for foreign denominated funds than a local borrower of equivalent creditworthiness. Consequently, two firms of equivalent creditworthiness can each exploit their, respective, name recognition by borrowing in their local capital market at a favorable rate and then re-lending at the same rate to the other.5. Discuss the risks confronting an interest rate and currency swap dealer.Answer: An interest rate and currency swap dealer confronts many different types of risk. Interest rate risk refers to the risk of interest rates changing unfavorably before the swap dealer can lay off on an opposing counterparty the unplaced side of a swap with another counterparty. Basis risk refers to the floating rates of two counterparties being pegged to two different indices. In this situation, since the indexes are not perfectly positively correlated, the swap bank may not always receive enough floating rate funds from one counterparty to pass through to satisfy the other side, while still covering its desired spread, or avoiding a loss. Exchange-rate risk refers to the risk the swap bank faces from fluctuating exchange rates during the time it takes the bank to lay off a swap it undertakes on an opposing counterparty before exchange rates change. Additionally, the dealer confronts credit risk from one counterparty defaulting and its having to fulfill the defaulting party’s obligation to the other counterparty. Mismatch risk refers to the difficulty of the dealer finding an exact opposite match for a swap it has agreed to take. Sovereign risk refers to a country imposing exchange restrictions on a currency involved in a swap making it costly, or impossible, for a counterparty to honor its swap obligations to the dealer. In this event, provisions exist for the early termination of a swap, which means a loss of revenue to the swap bank.6. Briefly discuss some variants of the basic interest rate and currency swaps diagramed in the chapter.Answer: Instead of the basic fixed-for-floating interest rate swap, there are also zero-coupon-for-floating rate swaps where the fixed rate payer makes only one zero-coupon payment at maturity on the notional value. There are also floating-for-floating rate swaps where each side is tied to a different floating rate index or a different frequency of the same index. Currency swaps need not be fixed-for-fixed; fixed-for-floating and floating-for-floating rate currency swaps are frequently arranged. Moreover, both currency and interest rate swaps can be amortizing as well as non-amortizing.7. If the cost advantage of interest rate swaps would likely be arbitraged away in competitive markets, what other explanations exist to explain the rapid development of the interest rate swap market?Answer: All types of debt instruments are not always available to all borrowers. Interest rate swaps can assist in market completeness. That is, a borrower may use a swap to get out of one type of financing and to obtain a more desirable type of credit that is more suitable for its asset maturity structure.8. Suppose Morgan Guaranty, Ltd. is quoting swap rates as follows: 7.75 - 8.10 percent annually against six-month dollar LIBOR for dollars and 11.25 - 11.65 percent annually against six-month dollar LIBOR for British pound sterling. At what rates will Morgan Guaranty enter into a $/£ currency swap?Answer: Morgan Guaranty will pay annual fixed-rate dollar payments of 7.75 percent against receiving six-month dollar LIBOR flat, or it will receive fixed-rate annual dollar payments at 8.10 percent against paying six-month dollar LIBOR flat. Morgan Guaranty will make annual fixed-rate £ payments at 11.25 percent against receiving six-month dollar LIBOR flat, or it will receive annual fixed-rate £ payments at 11.65 percent against paying six-month dollar LIBOR flat. Thus, Morgan Guaranty will enter into a currency swap in which it would pay annual fixed-rate dollar payments of 7.75 percent in return for receiving semi-annual fixed-rate £ payments at 11.65 percent, or it will receive annual fixed-rate dollar payments at 8.10 percent against paying annual fixed-rate £ payments at 11.25 percent.9. A U.S. company needs to raise €50,000,000. It plans to raise this money by issuing dollar-denominated bonds and using a currency swap to convert the dollars to euros. The company expects interest rates in both the United States and the euro zone to fall.a. Should the swap be structured with interest paid at a fixed or a floating rate?b. Should the swap be structured with interest received at a fixed or a floating rate?CFA Guideline Answer:a. The U.S. company would pay the interest rate in euros. Because it expects that the interest rate in the euro zone will fall in the future, it should choose a swap with a floating rate on the interest paid in euros to let the interest rate on its debt float down.b. The U.S. company would receive the interest rate in dollars. Because it expects that the interest rate in the United States will fall in the future, it should choose a swap with a fixed rate on the interest received in dollars to prevent the interest rate it receives from going down.*10. Assume a currency swap in which two counterparties of comparable credit risk each borrow at the best rate available, yet the nominal rate of one counterparty is higher than the other. After the initial principal exchange, is the counterparty that is required to make interest payments at the higher nominal rate at a financial disadvantage to the other in the swap agreement? Explain your thinking.Answer: Superficially, it may appear that the counterparty paying the higher nominal rate is at a disadvantage since it has borrowed at a lower rate. However, if the forward rate is an unbiased predictor of the expected spot rate and if IRP holds, then the currency with the higher nominal rate is expected to depreciate versus the other. In this case, the counterparty making the interest payments at the higher nominal rate is in effect making interest payments at the lower interest rate because the payment currency is depreciating in value versus the borrowing currency.PROBLEMS1. Alpha and Beta Companies can borrow for a five-year term at the following rates:Alpha BetaMoody’s credit rating Aa BaaFixed-rate borrowing cost 10.5% 12.0%Floating-rate borrowing cost LIBOR LIBOR + 1%a. Calculate the quality spread differential (QSD).b. Develop an interest rate swap in which both Alpha and Beta have an equal cost savings in their borrowing costs. Assume Alpha desires floating-rate debt and Beta desires fixed-rate debt. No swap bank is involved in this transaction.Solution:a. The QSD = (12.0% - 10.5%) minus (LIBOR + 1% - LIBOR) = .5%.b. Alpha needs to issue fixed-rate debt at 10.5% and Beta needs to issue floating rate-debt at LIBOR + 1%. Alpha needs to pay LIBOR to Beta. Beta needs to pay 10.75% to Alpha. If this is done, Alpha’s floating-rate all-in-cost is: 10.5% + LIBOR - 10.75% = LIBOR - .25%, a .25% savings over issuing floating-rate debt on its own. Beta’s fixed-rate all-in-cost is: LIBOR+ 1% + 10.75% - LIBOR = 11.75%, a .25% savings over issuing fixed-rate debt.2. Do problem 1 over again, this time assuming more realistically that a swap bank is involved as an intermediary. Assume the swap bank is quoting five-year dollar interest rate swaps at 10.7% - 10.8% against LIBOR flat.Solution: Alpha will issue fixed-rate debt at 10.5% and Beta will issue floating rate-debt at LIBOR + 1%. Alpha will receive 10.7% from the swap bank and pay it LIBOR. Beta will pay 10.8% to the swap bank and receive from it LIBOR. If this is done, Alpha’s floating-rate all-in-cost is: 10.5% + LIBOR - 10.7% = LIBOR - .20%, a .20% savings over issuing floating-rate debt on its own. Beta’s fixed-rate all-in-cost is: LIBOR+ 1% + 10.8% - LIBOR = 11.8%, a .20% savings over issuing fixed-rate debt.3. Company A is a AAA-rated firm desiring to issue five-year FRNs. It finds that it can issue FRNs at six-month LIBOR + .125 percent or at three-month LIBOR + .125 percent. Given its asset structure, three-month LIBOR is the preferred index. Company B is an A-rated firm that also desires to issue five-year FRNs. It finds it can issue at six-month LIBOR + 1.0 percent or at three-month LIBOR + .625 percent. Given its asset structure, six-month LIBOR is the preferred index. Assume a notional principal of $15,000,000. Determine the QSD and set up a floating-for-floating rate swap where the swap bank receives .125 percent and the two counterparties share the remaining savings equally.Solution: The quality spread differential is [(Six-month LIBOR + 1.0 percent) minus (Six-month LIBOR + .125 percent) =] .875 percent minus [(Three-month LIBOR + .625 percent) minus (Three-month LIBOR + .125 percent) =] .50 percent, which equals .375 percent. If the swap bank receives .125 percent, each counterparty is to save .125 percent. To affect the swap, Company A would issue FRNs indexed to six-month LIBOR and Company B would issue FRNs indexed three-month LIBOR. Company B might make semi-annual payments of six-month LIBOR + .125 percent to the swap bank, which would pass all of it through to Company A. Company A, in turn, might make quarterly payments of three-month LIBOR to the swap bank, which would pass through three-month LIBOR - .125 percent to Company B. On an annualized basis, Company B will remit to the swap bank six-month LIBOR + .125 percent and pay three-month LIBOR + .625 percent on its FRNs. It will receive three-month LIBOR - .125 percent from the swap bank. This arrangement results in an all-in cost of six-month LIBOR + .825 percent, which is a rate .125 percent below the FRNs indexed to six-month LIBOR + 1.0 percent Company B could issue on its own. Company A will remit three-month LIBOR to the swap bank and pay six-month LIBOR + .125 percent on its FRNs. It will receive six-month LIBOR + .125 percent from the swap bank. This arrangement results in an all-in cost of three-month LIBOR for Company A, which is .125 percent less than the FRNs indexed to three-month LIBOR + .125 percent it could issue on its own. The arrangements with the two counterparties net the swap bank .125 percent per annum, received quarterly.*4. A corporation enters into a five-year interest rate swap with a swap bank in which it agrees to pay the swap bank a fixed rate of 9.75 percent annually on a notional amount of €15,000,000 and receive LIBOR. As of the second reset date, determine the price of the swap from the corporation’s viewpoint assuming that the fixed-rate side of the swap has increased to 10.25 percent.Solution: On the reset date, the present value of the future floating-rate payments the corporation will receive from the swap bank based on the notional value will be €15,000,000. The present value of a hypothetical bond issue of €15,000,000 with three remaining 9.75 percent coupon payments at the newfixed-rate of 10.25 percent is €14,814,304. This sum represents the present value of the remaining payments the swap bank will receive from the corporation. Thus, the swap bank should be willing to buy and the corporation should be willing to sell the swap for €15,000,000 - €14,814,304 = €185,696.5. Karla Ferris, a fixed income manager at Mangus Capital Management, expects the current positively sloped U.S. Treasury yield curve to shift parallel upward.Ferris owns two $1,000,000 corporate bonds maturing on June 15, 1999, one with a variable rate based on 6-month U.S. dollar LIBOR and one with a fixed rate. Both yield 50 basis points over comparable U.S. Treasury market rates, have very similar credit quality, and pay interest semi-annually.Ferris wished to execute a swap to take advantage of her expectation of a yield curve shift and believes that any difference in credit spread between LIBOR and U.S. Treasury market rates will remain constant.a. Describe a six-month U.S. dollar LIBOR-based swap that would allow Ferris to take advantage of her expectation. Discuss, assuming Ferris’ expectation is correct, the change in the swap’s value and how that change would affect the value of her portfolio. [No calculations required to answer part a.] Instead of the swap described in part a, Ferris would use the following alternative derivative strategy to achieve the same result.b. Explain, assuming Ferris’ expectation is correct, how the following strategy achieves the same result in response to the yield curve shift. [No calculations required to answer part b.]Date Nominal Eurodollar Futures Contract ValueSettlement12-15-97 $1,000,00003-15-98 1,000,00006-15-98 1,000,00009-15-98 1,000,00012-15-98 1,000,00003-15-99 1,000,000c. Discuss one reason why these two derivative strategies provide the same result.CFA Guideline Answera.The Swap Value and its Effect on Ferris’ PortfolioBecause Karla Ferris believes interest rates will rise, she will want to swap her $1,000,000 fixed-rate corporate bond interest to receive six-month U.S. dollar LIBOR. She will continue to hold her variable-rate six-month U.S. dollar LIBOR rate bond because its payments will increase as interest rates rise. Because the credit risk between the U.S. dollar LIBOR and the U.S. Treasury market is expected to remain constant, Ferris can use the U.S. dollar LIBOR market to take advantage of her interest rate expectation without affecting her credit risk exposure.To execute this swap, she would enter into a two-year term, semi-annual settle, $1,000,000 nominal principal, pay fixed-receive floating U.S. dollar LIBOR swap. If rates rise, the swap’s mark-to-market value will increase because the U.S. dollar LIBOR Ferris receives will be higher than the LIBOR rates from which the swap was priced. If Ferris were to enter into the same swap after interest rates rise, she would pay a higher fixed rate to receive LIBOR rates. This higher fixed rate would be calculated as the present value of now higher forward LIBOR rates. Because Ferris would be paying a stated fixed rate that is lower than this new higher-present-value fixed rate, she could sell her swap at a premium. This premium is called the “replacement cost” value of the swap.b. Eurodollar Futures StrategyThe appropriate futures hedge is to short a combination of Eurodollar futures contracts with different settlement dates to match the coupon payments and principal. This futures hedge accomplishes the same objective as the pay fixed-receive floating swap described in Part a. By discussing how the yield-curve shift affects the value of the futures hedge, the candidate can show an understanding of how Eurodollar futures contracts can be used instead of a pay fixed-receive floating swap.If rates rise, the mark-to-market values of the Eurodollar contracts decrease; their yields must increase to equal the new higher forward and spot LIBOR rates. Because Ferris must short or sell the Eurodollar contracts to duplicate the pay fixed-receive variable swap in Part a, she gains as the Eurodollar futures contracts decline in value and the futures hedge increases in value. As the contracts expire, or if Ferris sells the remaining contracts prior to maturity, she will recognize a gain that increases her return. With higher interest rates, the value of the fixed-rate bond will decrease. If the hedge ratios are appropriate, the value of the portfolio, however, will remain unchanged because of the increased value of the hedge, which offsets the fixed-rate bond’s decrease.c. Why the Derivative Strategies Achieve the Same ResultArbitrage market forces make these two strategies provide the same result to Ferris. The two strategies are different mechanisms for different market participants to hedge against increasing rates. Some money managers prefer swaps; others, Eurodollar futures contracts. Each institutional marketparticipant has different preferences and choices in hedging interest rate risk. The key is that market makers moving into and out of these two markets ensure that the markets are similarly priced and provide similar returns. As an example of such an arbitrage, consider what would happen if forward market LIBOR rates were lower than swap market LIBOR rates. An arbitrageur would, under such circumstances, sell the futures/forwards contracts and enter into a received fixed-pay variable swap. This arbitrageur could now receive the higher fixed rate of the swap market and pay the lower fixed rate of the futures market. He or she would pocket the differences between the two rates (without risk and without having to make any [net] investment.) This arbitrage could not last.As more and more market makers sold Eurodollar futures contracts, the selling pressure would cause their prices to fall and yields to rise, which would cause the present value cost of selling the Eurodollar contracts also to increase. Similarly, as more and more market makers offer to receive fixed rates in the swap market, market makers would have to lower their fixed rates to attract customers so they could lock in the lower hedge cost in the Eurodollar futures market. Thus, Eurodollar forward contract yields would rise and/or swap market receive-fixed rates would fall until the two rates converge. At this point, the arbitrage opportunity would no longer exist and the swap and forwards/futures markets would be in equilibrium.6. Rone Company asks Paula Scott, a treasury analyst, to recommend a flexible way to manage the company’s financial risks.Two years ago, Rone issued a $25 million (U.S.$), five-year floating rate note (FRN). The FRN pays an annual coupon equal to one-year LIBOR plus 75 basis points. The FRN is non-callable and will be repaid at par at maturity.Scott expects interest rates to increase and she recognizes that Rone could protect itself against the increase by using a pay-fixed swap. However, Rone’s Board of Directors prohibits both short sales of securities and swap transactions. Scott decides to replicate a pay-fixed swap using a combination of capital market instruments.a. Identify the instruments needed by Scott to replicate a pay-fixed swap and describe the required transactions.b. Explain how the transactions in Part a are equivalent to using a pay-fixed swap.CFA Guideline Answera. The instruments needed by Scott are a fixed-coupon bond and a floating rate note (FRN).The transactions required are to:· issue a fixed-coupon bond with a maturity of three years and a notional amount of $25 million, and· buy a $25 million FRN of the same maturity that pays one-year LIBOR plus 75 bps.b. At the outset, Rone will issue the bond and buy the FRN, resulting in a zero net cash flow at initiation. At the end of the third year, Rone will repay the fixed-coupon bond and will be repaid the FRN, resulting in a zero net cash flow at maturity. The net cash flow associated with each of the three annual coupon payments will be the difference between the inflow (to Rone) on the FRN and the outflow (to Rone) on the bond. Movements in interest rates during the three-year period will determine whether the net cash flow associated with the coupons is positive or negative to Rone. Thus, the bond transactions are financially equivalent to a plain vanilla pay-fixed interest rate swap.7. A company based in the United Kingdom has an Italian subsidiary. The subsidiary generates €25,000,000 a year, received in equivalent semiannual installments of €12,500,000. The British company wishes to convert the euro cash flows to pounds twice a year. It plans to engage in a currency swap in order to lock in the exchange rate at which it can convert the euros to pounds. The current exchange rate is €1.5/£. The fixed rate on a plain vaninilla currency swap in pounds is 7.5 percent per year, and the fixed rate on a plain vanilla currency swap in euros is 6.5 percent per year.a. Determine the notional principals in euros and pounds for a swap with semiannual payments that will help achieve the objective.b. Determine the semiannual cash flows from this swap.CFA Guideline Answera. The semiannual cash flow must be converted into pounds is €25,000,000/2 = €12,500,000. In order to create a swap to convert €12,500,000, the equivalent notional principals are · Euro notional principal = €12,500,000/(0.065/2) = €384,615,385· Pound notional principal = €384,615,385/€1.5/£ = £256,410,257b. The cash flows from the swap will now be· Company makes swap payment = €384,615,385(0.065/2) = €12,500,000· Company receives swap payment = £256,410,257(0.075/2) = £9,615,385The company has effectively converted euro cash receipts to pounds.8. Ashton Bishop is the debt manager for World Telephone, which needs €3.33 billion Euro financing for its operations. Bishop is considering the choice between issuance of debt denominated in: ∙ Euros (€), or∙ U.S. dollars, accompanied by a combined interest rate and currency swap.a. Explain one risk World would assume by entering into the combined interest rate and currency swap.Bishop believes that issuing the U.S.-dollar debt and entering into the swap can lower World’s cost of debt by 45 basis points. Immediately after selling the debt issue, World would swap the U.S. dollar payments for Euro payments throughout the maturity of the debt. She assumes a constant currency exchange rate throughout the tenor of the swap.Exhibit 1 gives details for the two alternative debt issues. Exhibit 2 provides current information about spot currency exchange rates and the 3-year tenor Euro/U.S. Dollar currency and interest rate swap.Exhibit 1World Telephone Debt DetailsCharacteristic Euro Currency Debt U.S. Dollar Currency DebtPar value €3.33 billion $3 billionTerm to maturity 3 years 3 yearsFixed interest rate 6.25% 7.75%Interest payment Annual AnnualExhibit 2Currency Exchange Rate and Swap InformationSpot currency exchange rate $0.90 per Euro ($0.90/€1.00)3-year tenor Euro/U.S. Dollarfixed interest rates 5.80% Euro/7.30% U.S. Dollarb. Show the notional principal and interest payment cash flows of the combined interest rate and currency swap.Note: Your response should show both the correct currency ($ or €) and amount for each cash flow. Answer problem b in the template provided.Template for problem bc. State whether or not World would reduce its borrowing cost by issuing the debt denominated in U.S. dollars, accompanied by the combined interest rate and currency swap. Justify your response with one reason.CFA Guideline Answera. World would assume both counterparty risk and currency risk. Counterparty risk is the risk that Bishop’s counterparty will default on payment of principal or interest cash flows in the swap.Currency risk is the currency exposure risk associated with all cash flows. If the US$ appreciates (Euro depreciates), there would be a loss on funding of the coupon payments; however, if the US$ depreciates, then the dollars will be worth less at the swap’s maturity.b.0 YearYear32 Year1 YearWorld paysNotional$3 billion €3.33 billion PrincipalInterest payment €193.14 million1€193.14 million €193.14 million World receives$3.33 billion €3 billion NotionalPrincipalInterest payment $219 million2$219 million $219 million1 € 193.14 million = € 3.33 billion x 5.8%2 $219 million = $3 billion x 7.3%c. World would not reduce its borrowing cost, because what Bishop saves in the Euro market, she loses in the dollar market. The interest rate on the Euro pay side of her swap is 5.80 percent, lower than the 6.25 percent she would pay on her Euro debt issue, an interest savings of 45 bps. But Bishop is only receiving 7.30 percent in U.S. dollars to pay on her 7.75 percent U.S. debt interest payment, an interest shortfall of 45 bps. Given a constant currency exchange rate, this 45 bps shortfall exactly offsets the savings from paying 5.80 percent versus the 6.25 percent. Thus there is no interest cost savings by sellingthe U.S. dollar debt issue and entering into the swap arrangement.MINI CASE: THE CENTRALIA CORPORATION’S CURRENCY SWAPThe Centralia Corporation is a U.S. manufacturer of small kitchen electrical appliances. It has decided to construct a wholly owned manufacturing facility in Zaragoza, Spain, to manufacture microwave ovens for sale in the European Union. The plant is expected to cost €5,500,000, and to take about one year to complete. The plant is to be financed over its economic life of eight years. The borrowing capacity created by this capital expenditure is $2,900,000; the remainder of the plant will be equity financed. Centralia is not well known in the Spanish or international bond market; consequently, it would have to pay 7 percent per annum to borrow euros, whereas the normal borrowing rate in the euro zone for well-known firms of equivalent risk is 6 percent. Alternatively, Centralia can borrow dollars in the U.S. at a rate of 8 percent.Study Questions1. Suppose a Spanish MNC has a mirror-image situation and needs $2,900,000 to finance a capital expenditure of one of its U.S. subsidiaries. It finds that it must pay a 9 percent fixed rate in the United States for dollars, whereas it can borrow euros at 6 percent. The exchange rate has been forecast to be $1.33/€1.00 in one year. Set up a currency swap that will benefit each counterparty.*2. Suppose that one year after the inception of the currency swap between Centralia and the Spanish MNC, the U.S. dollar fixed-rate has fallen from 8 to 6 percent and the euro zone fixed-rate for euros has fallen from 6 to 5.50 percent. In both dollars and euros, determine the market value of the swap if the exchange rate is $1.3343/€1.00.Suggested Solution to The Centralia Corporation’s Currency Swap1. The Spanish MNC should issue €2,180,500 of 6 percent fixed-rate debt and Centralia should issue $2,900,000 of fixed-rate 8 percent debt, since each counterparty has a relative comparative advantage in their home market. They will exchange principal sums in one year. The contractual exchange rate for the initial exchange is $2,900,000/€2,180,500, or $1.33/€1.00. Annually the counterparties will swap debt service: the Spanish MNC will pay Centralia $232,000 (= $2,900,000 x .08) and Centralia will pay the Spanish MNC €130,830 (= €2,180,500 x .06). The contractual exchange rate of the first seven annual debt service exchanges is $232,000/€130,830, or $1.7733/€1.00. At maturity, Centralia and the Spanish MNC will re-exchange the principal sums and the final debt service payments. The contractual exchange rate of the final currency exchange is $3,132,000/€2,311,330 = ($2,900,000 + $232,000)/(€2,180,500 + €130,830), or $1.3551/€1.00.*2. The market value of the dollar debt is the present value of a seven-year annuity of $232,000 and a lump sum of $2,900,000 discounted at 6 percent. This present value is $3,223,778. Similarly, the market value of the euro debt is the present value of a seven-year annuity of €130,830 and a lump sum of €2,180,500 discounted at 5.50 percent. This present value is €2,242,459. The dollar value of the swap is $3,223,778 - €2,242,459 x 1.3343 = $231,665. The euro value of the swap is €2,242,459 - $3,223,778/1.3343 = -€173,623.。

参考答案-final

1、写一个MATLAB 小程序，求出最大的n 值，使得n!<realmax >> s=1;n=0;>>while (s<realmax) n=n+1; s=s*n; end >> n-1 n = 1702、写一个MATLAB 函数myfun.m 来计算下列方程式：y=0.5*exp(x/3)-x*x*sin(x)其中x 是函数的输入，y 是函数的输出。

你的函数必须能处理当x 是标量或向量的两种情况。

>> syms x;>> myfun=@(x,y)0.5.*exp(x./3)-x.*x.*sin(x); >> y=myfun(x);3、一个平面上的椭圆可以表示成下列方程式：1)/()/(22=+b y a x 。

我们也可以用参数将椭圆表示成：x=a*cos(θ) y=b*sin(θ)。

请利用上述参数式，画出一个椭圆，其中a=5,b=3，而且椭圆上共有100个点。

>> theta = [0 : 2*pi/100 : 2*pi]; >> a=3; >> b=5;>> x=a.*cos(theta); >> y=b.*sin(theta); >> plot(x,y, '.')4、一条参数式的曲线可由下列方程式表示：x=sin(-t)+t y=1-cos(-t)当t 由0变化到4*pi 时，画出此曲线在XY 平面的轨迹。

>> t=[0:4*pi/200:4*pi]; >> x=sin(-t)+t; >> y=1-cos(-t); >> plot(x,y,’.’)5、请用meshc 命令来同时画出下列函数的曲面图和等高线图：z=xy/(x+y)。

其中x 和y 都介于0和1之间，且各自都分成21个栅格点，所以此曲面共有441个点。

《审计学》习题及答案第十四章政府审计(2)

第十四章政府审计（2）一、单项选择题1.（）是对审计机关和审计人员应当具备的基本条件和职业要求的规定。

A.一般准则B.作业准则C.报告准则D.审计报告处理准则2.“审计法规定，各级审计机关对本级预算执行情况进行审计监督后，要向本级政府提交审计结果报告”说的是财政收支审计的哪一个特点（）。

A.审计主体的单一性B.审计范围的广泛性C.审计报告制度的法定性D.审计结果的高风险性3.政府审计活动是具有（）的国家经济监督活动，被审计单位必须积极配合。

A.高层次B.强制性C.独立性D.权威性4.（）不是以本部门的收益为目标，而是以维护政府和全体人民利益为目标的审计。

A.政府审计B.民间审计C.内部审计D.国际审计5.以下哪一项是财政收支审计.事业单位财务收支审计以及建设项目财务收支审计共有的特点（）。

A.审计报告制度的法定性B.审计过程的阶段性C.审计监督事前性D.审计范围的广泛性二、多项选择题1.财政收支审计的特点包括（）。

A.审计主体的单一性B.审计范围的广泛性C.审计报告制度的法定性D.审计结果的高风险性2.国家基本审计准则由以下哪些内容构成（）。

A.一般准则B.作业准则C.报告准则D.审计报告处理准则3.事业单位财务收支审计的特点有（）。

A.审计监督事前性B.审计范围的覆盖广C.审计方式多样化D.审计处理难度大4.企业单位财务收支审计的特点主要体现在以下哪些方面（）。

A.政府审计的启动具有强制性B.政府审计是无偿审计C.政府审计结果可强制执行D.政府审计只具有单向独立性5.建设项目财务收支审计的特点有（）。

A.审计过程的阶段性B.审计内容的复杂性C.审计范围的广泛性D.审计方法的技术性三、判断题1.政府审计是依照宪法实施的任意审计，具有很高的权威性。

（）2.政府审计和国家审计是两个完全不同的概念，绝不能相混淆。

（）3.政府审计具有很高的独立性，体现为双向独立。

（）4.政府审计的强制性既体现在审计程序的启动环节，又体现在审计结果的执行上。

1、下载文档前请自行甄别文档内容的完整性，平台不提供额外的编辑、内容补充、找答案等附加服务。
2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
3、如文档侵犯您的权益，请联系客服反馈,我们会尽快为您处理(人工客服工作时间：9:00-18:30)。

精品文档精品文档 1、电子束入射固体样品表面会激发哪些信号？它们有哪些特点和用途？答：具有高能量的入射电子束与固体样品表面的原子核以及核外电子发生作用，产生下图所示的物理信号：

① 背散射电子背散射电子是指被固体样品中的原子核反弹回来的一部分入射电子，其中包括弹性背散射电子和非弹性背散射电子。弹性背散射电子是指被样品中原子核反弹回来的散射角大于90°的那些入射电子，其能量基本上没有变化。非弹性背散射电子是入射电子和核外电子撞击后产生非弹性散射而造成的，不仅能量变化，方向也发生变化。背散射电子来自样品表层几百纳米的深度范围。由于背散射电子的产额随原子序数的增加而增加，所以，利用背散射电子作为成像信号不仅能分析形貌特征，也可用来显示原子序数衬度，定性地进行成分分析。 ② 二次电子二次电子是指被入射电子轰击出来的核外电子。二次电子来自表面50-500 Å的区域，能量为0-50 eV。它对试样表面状态非常敏感，能有效地显示试样表面的微观形貌。由于它发自试样表面层，入射电子还没有较多次散射，因此产生二次电子的面积与入射电子的照射面积没多大区别。所以二次电子的分辨率较高，一般可达到50-100 Å。扫描电子显微镜的分辨率通常就是二次电子分辨率。二次电子产额随原子序数的变化不明显，它主要决定于表面形貌。 ③ 吸收电子入射电子进入样品后，经多次非弹性散射，能量损失殆尽（假定样品有足够厚度，没有透射电子产生），最后被样品吸收，此即为吸收电子。入射电子束射入一含有多元素的样品时，由于二次电子产额不受原子序数影响，则产生背散射电子较多的部位其吸收电子的数量就较少。因此，吸收电流像可以反映原子序数衬度，同样也可以用来进行定性的微区成分分析。 ④ 透射电子如果样品厚度小于入射电子的有效穿透深度，那么就会有相当数量的入射电子能够穿过薄样品而成为透射电子。一般用它对薄样品进行成像和衍射分析。样品下方检测到的透射电子信号中，除了有能量与入射电子相当的弹性散射电子外，还有各种不同能量损失的非弹性散射电子。其中有些待征能量损失ΔE的非弹性散射电子和分析区域的成分有关，因此，可以用特征能量损失电子配合电子能量分析器来进行微区成分分析。 ⑤ 特性X射线特征X射线是原子的内层电子受到激发以后，在能级跃迁过程中直接释放的具有特征能量和波长的一种电磁波辐射。发射的X射线波长具有特征值，波长和原子序数之间服从莫塞莱定律。因此，原子序数和特征能量之间是有对应关系的，利用这一对应关系可以进行成分分析。如果用X射线探测器测到了样品微区中存在某一特征波长，就可以判定该微区中存在的相应元素。 ⑥ 俄歇电子精品文档精品文档如果原子内层电子能级跃迁过程中释放出来的能量不以X射线的形式释放，而是用该能量将核外另一电子打出，脱离原子变为二次电子，这种二次电子叫做俄歇电子。因为每一种原子都有自己特定的壳层能量，所以它们的俄歇电子能量也各有特征值，一般在50-1500 eV范围之内。俄歇电子是由试样表面极有限的几个原子层中发出的，这说明俄歇电子信号适用于表层化学成分分析。

2、扫描电镜的分辨率受哪些因素影响，用不同的信号成像时，其分辨率有何不同？所谓扫描电镜的分辨率是指用何种信号成像时的分辨率？答：在其他条件相同的情况下（如信噪比、磁场条件及机械振动等）电子束束斑大小，检测信号的类型，检测部位的原子序数是影响扫描电镜分辨率的三大因素。用不同信号成像，其分辨率相差较大，列表说明：

所谓扫描电镜的分辨率是指用二次电子信号成像时的分辨率。 3、扫描电镜的成像原理与透时电镜有何不同？答：两者完全不同。透射电镜用电磁透镜放大成像，而扫描电镜则是以类似电视机摄影显像的方式，利用细聚焦电子束在样品表面扫描时激发出的各种物理信号来调制而成。

4、二次电子像和背散射电子像在显示表面形貌衬度时有何相同与不同之处? 答：相同处：均利用电子信号的强弱来行成形貌衬度不同处： ① 分辨率不同。背散射电子是在一个较大的作用体积内被入射电子激发出来的，成像单元较大，因而分辨率较二次电子像低。 ② 能量和运动轨迹不同。背散射电子能量较高，以直线逸出，因而样品背部的电子无法被检测到，成一片阴影，衬度较大，无法分析细节；利用二次电子作形貌分析时，可以利用在检测器收集光栅上加上正电压来吸收较低能量的二次电子，使样品背部及凹坑等处逸出的电子以弧线状运动轨迹被吸收，因而使图像层次增加，细节清晰。

5、说明背散射电子像和吸收电子像的原子序数衬度形成原理，并举例说明在分析样品中元素元素分布的应用。答：右图显示原子序数对背散射电子产额的影响。随着原子序数Z增大，产额增大。样品表面平均原子序数大的微区，背散射电子信号强度较高，可以根据背散射电子像的亮暗衬度来判断相应区域原子序数的相对高低，对金属及其合金进行定性成分分析。

吸收电子也是对样品中原子序数敏感的一种物理信号。由入射电子束于样品的相互作用可知：iI =iB+iA+iT+iS式中，iI 是入射电子流，iB，iT和iS分别代表背散射电子，透射电子，二次电子的电流，而iA为吸收电子电流。对

信号二次电子背散射电子吸收电子特征X射线俄歇电子分辨率（nm） 5~10 50~200 100~1000 100~1000 5~10 精品文档

精品文档于样品厚度足够大时，入射电子不能穿透样品，所以透射电子电流为零，这时的入射电子电流可表示为：iI =iB+iA +iS，由于二次电子信号与原子序数无关（可设iS=C），则吸收电子电流为：iA = (iI -C) - iB在一定条件下，入射电子束电流是一定的，所以吸收电流与背散射电流存在互补关系。因此，吸收电子像的衬度是与背散射电子和二次电子的衬度互补的。所以，背散射电子图像上的亮区在相应的吸收电子图像上必定是暗区。

奥氏体铸铁的显微组织 (a)背散射电子像 (b)吸收电子像在图上可以看出，在背散射电子像上的石墨条呈现暗的衬度，而在吸收电子像上呈现亮的衬度。

6、当电子束入射重元素和轻元素时，其作用体积有何不同？各自产生的信号分辨率有何特点？答：作用体积分辨率轻元素滴状高精品文档精品文档重元素半球状低 ① 轻元素：电子束进入轻元素样品表面后会造成一个滴状作用体积。入射电子束在被样品吸收或散射出样品表面之前将在这个体积中活动。俄歇电子和二次电子因其本身能量较低以及平均自由程很短，只能在样品的浅层表面内逸出，在一般情况下能激发出俄歇电子的样品表层厚度约为0.5-2nm，激发二次电子的层深为5-10nm范围。入射电子束进入浅层表面时，尚未向横向扩展开来，因此，俄歇电子和二次电子只能在一个和入射电子束斑直径相当的圆柱体内被激发出来，因为束斑直径就是一个成像检测单元（像点）的大小，所以这两种电子的分辨率就相当于束斑的直径。 ② 重元素：电子束入射重元素样品中时，作用体积不呈滴状，而是半球状。电子束进入表面后立即向横向扩展，因此在分析重元素时，即使电子束的束斑很细小，也不能达到较高的分辨率，此时二次电子的分辨率和背散射电子的分辨率之间的差距明显变小。

7、二次电子像景深很大，样品凹坑底部都能清楚地显示出来，从而使图像的立体感很强，其原因何在? 答：用二次电子信号作形貌分析时，在检测器收集栅上加以一定大小的正电压（一般为250-500V），来吸引能量较低的二次电子，使它们以弧线路线进入闪烁体，这样在样品表面某些背向检测器或凹坑等部位上逸出的二次电子也对成像有所贡献，图像景深增加，细节清楚。

一、选择题 1、仅仅反映固体样品表面形貌信息的物理信号是（ B ）。 A. 背散射电子；B. 二次电子；C. 吸收电子；D.透射电子。

2、在扫描电子显微镜中，下列二次电子像衬度最亮的区域是（ B ）。 A.和电子束垂直的表面；B. 和电子束成30º的表面；C. 和电子束成45º的表面；D. 和电子束成60º的表面。 3、可以探测表面1nm层厚的样品成分信息的物理信号是（ D ）。 A. 背散射电子；B. 吸收电子；C. 特征X射线；D. 俄歇电子。

二、判断题 1、扫描电子显微镜中的物镜与透射电子显微镜的物镜一样。（× ）

2、扫描电子显微镜的分辨率主要取决于物理信号而不是衍射效应和球差。（√ ） 3、扫描电子显微镜的衬度和透射电镜一样取决于质厚衬度和衍射衬度。（× ）

4、扫描电子显微镜具有大的景深，所以它可以用来进行断口形貌的分析观察。（√ ）

三、填空题 1、电子束与固体样品相互作用可以产生背散射电子、二次电子、透射电子、特征X射线、俄歇电子、吸收电子等物理信号。精品文档精品文档 2、扫描电子显微镜的放大倍数是阴极射线电子束在荧光屏上的扫描宽度与电子枪电子束在样品表面的扫描宽度的比值。在衬度像上颗粒、凸起的棱角是亮衬度，而裂纹、凹坑则是暗衬度。

3、分辨率最高的物理信号是俄歇电子或二次电子为 5 nm，分辨率最低的物理信号是特征X射线为 100 nm以上。

4、扫描电镜的分辨率是指二次电子信号成像时的分辨率 5、扫描电子显微镜可以替代金相显微镜进行材料金相观察，也可以对断口进行分析观察。

6、扫描电子显微镜常用的信号是二次电子和背散射电子。 7、扫描电子显微镜是电子光学系统，信号收集处理、图像显示和记录系统，真空系统三个基本部分组成。 8、电子光学系统包括电子枪、电磁透镜、扫描线圈和样品室。

四、名词解释 1、背散射电子：入射电子被样品原子散射回来的部分；它包括弹性散射和非弹性

散射部分；背散射电子的作用深度大，产额大小取决于样品原子种类和样品形状。 2、吸收电子：入射电子进入样品后，经多次非弹性散射，能量损失殆尽（假定样品有足够厚度，没有透射电子产生），最后被样品吸收。吸收电流像可以反映原子序数衬度，同样也可以用来进行定性的微区成分分析。 3、特征X射线：原子的内层电子受到激发以后，在能级跃迁过程中直接释放的具有特征能量和波长的一种电磁波辐射。利用特征X射线可以进行成分分析。

4、二次电子：二次电子是指被入射电子轰击出来的核外电子。二次电子来自表面

50-100 Å的区域，能量为0-50 eV。它对试样表面状态非常敏感，能有效地显示试样表面的微观形貌。 5、俄歇电子：如果原子内层电子能级跃迁过程中释放出来的能量不以X射线的形式释放，而是用该能量将核外另一电子打出，脱离原子变为二次电子，这种二次电子叫做俄歇电子。俄歇电子信号适用于表层化学成分分析。

五、问答题 1、扫描电子显微镜有哪些特点？答：和光学显微镜相比，扫描电子显微镜具有能连续改变放大倍率，高放大倍数，高分辨率的优点；扫描电镜的景深很大，特别适合断口分析观察；背散射电子成像还可以显示原子序数衬度。和透射电子显微镜相比，扫描电镜观察的是表面形貌，样品制备方便简单。

最新第十四章习题答案final

八年级数学上册《第十四章 公式法》练习题附答案-人教版