[自学考试] 《大学英语自学教程》(上册)课后习题答案
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《大学英语自学教程》（上册）课后习题答案
Unit 1
Text A
Exercises for the Text
I. 1.d 2.a 3.c 4.d 5.d
II.
1.task
2.intelligent
3.research
4.clue
5.conclusion
6.repeat
https://www.360docs.net/doc/145428358.html,municate
8.purpose
9.probably 10.outline
III.
1.Instead of
2.therefore
3.more...than
4.even
5.First of all
6.because
7.on the other hand
8.finally
9.looking for 10.Conversely
IV.
1.Research shows that successful language learners are similar in many ways.
https://www.360docs.net/doc/145428358.html,nguage learning is active learning.Therefore,successful learners should look for e very chance to use the language.
https://www.360docs.net/doc/145428358.html,nguage learning should be active,independent and purposeful.
4.Learning a language is different from learning maths.
5.The teacher often imparts successfull language learning experiences to us. Vocabulary Exercises
I.
1.a.success b.successful c.successfully
2.a.indepence b.depend c.dependent
3.a.covered b.uncover c.discovered
4.a.purposeful b .purposefully c.purpose II.
1.inexact
2.technique
3.outlined
https://www.360docs.net/doc/145428358.html,municate
5.regularly
6.clues
7.intelligent
8.incomplete
9.similar 10.statement
III. 1.disagree 2.independent 3.incomplete 4.inexact 5.uncover
IV.
1.They find it hard to master a foreign language.
2.The research shows that successful men are similar in many ways.
3.Successful language learners do not only depend on the book or the teacher.
4.We are willingto help our friends.
5.We should learn new things independently,actively,and purposefully.
Text B Exercises for the Text
I. 1.T 2.F 3.T 4.F 5.T 6.F 7.F 8.F 9.T 10.F
II.
1.With the help of their fingers
2."I am thirsty."
3.tea,coffee,wine,beer and soda-water
4.Put his hands on his stomach
5.nothing but drinks
6.much more exact
7.meanings and can be put together into sentences
8.form new sentences
9.talk
10.speak
Vocabulary Exercises
I. 1.b 2.a 3.c 4.e 5.d
II. 1.B 2.A 3.B 4.D 5.A 6.A 7.C 8.C 9.C 10.B
Grammar Exercises
I.
whether 连词 towards 介词second 数词 hour 名词repeat 动词successful 形容词not 副词 probably 副词than 连词 because 连词
which 连词 even 副词intelligent 形容词 differ 动词regular 形容词some 形容词/代词/副词into 介词 oh 感叹词seem 系动词 communicate 动词II.
1.Let 动词 round 介词
2.fresh 形容词 for 介词
3.leave 名词 call 动词 on 介词 if 连词 spare 动词
4.Even 副词 it 代词
5.Where 连接副词 will 名词
6.after 介词 calm 名词
7.seem 系动词 those 代词 makes 名词
8.without 介词 return 名词
9.strict 形容词 work 动词
10.news 名词 live 形容词 meeting 名词
III.
(斜体为主语，带下划线的为谓语）
1.Most adults would disagree with this statement.
2.How much time did they allow you for doing the work.
3. I had a visit from Mary yesterday.
4. China's stand on this questionis clear to all.
5.Warm clothes protest against the cold of winter.
6.What we need is more practice.
7.There doesn't seem to be much chance of my getting job.
8.In those days the cost of living rose by nearly 4 percent.
9.There are a number of people interested in the case.
10.Every means has been tried but without much result.
IV.
1.a magazine (宾语）last night （状语）
2.in need (定语）indeed (定语）
3.outside your area (定语）telephoning long distance （主语补足语）
4.your children (宾语）all day （状语）
5.his direction （宾语）French （宾语）
6.me (宾语）plenty of exercises (不定式宾语）
7.long (宾语）to London （状语）
8.those (宾语）who help themselves (从句作定语）
9.her （宾语）above others （宾语补足语）
10.to build a hotel in the village (定语）of the foreigners （定语）
Unit 2
Text A
Exercises for the Text
I.
1.a
2.c
3.a
4.a
5.c
II.
1. Income tax is a certain percentage of the salaries paid to the goverment.
2. Graduated income tax means the percentage of the tax(14 to 70 percent) increases a s a person's income increase.
3. Property tax is that people who own a home have to pay taxes on it.
4. Exercise tax is charged on cars in a city.
5. Sales tax is a percentage charged to any item which you buy in that state.
III.
1.due
2.depends on
3.diverse
4.consists of
5.simila
6.tends to
https://www.360docs.net/doc/145428358.html,plaining abou t
8.In addition to
9.issue 10.agreed on
IV.
1.How much do you charge for a haircut.
2.We are trying to use funds for the Red Cross.
3.He has earned a good reputation for honsety.
4.We pay taxes in exchange for government services.
5.An open letter protests the government's foreign policy.
V.
1.Every citizen is obliged to pay taxes.(It is obligatory on every citizen to pay taxes)(I t is every citizen's duty to pay taxes.)
2.Americans often say that there are two things they can be sure of in life.
3.There are generally three levels of government in the United States; therefore,ther
e are three types o
f taxes.
4.Some states charge income tax in addition to a sales tax.
5.Americans complain that taxes are too high and the government uses them in the wr ong way.
Vocabulary Exercises
I.
1.a. percent b. percentage c. percent
2.a. adds b. addition c. additional
3.a. confused b. confusing c. confusion
4.a. complained b. complain c. complaint
II.
1.charge
2.departmen
3.due
4.diverse
5.earns
6.vary
7.property
8.leading
9.fund s 10.tends
III.
1.China leads the world with silk products.
2.In addition to an income tax some states charge a sales tax.
3.The sales tax varies from price to price of any item you buy.
4.People often complain about the increasing price.
5.His mother says that he spends too much time on TV every day.
Text B
Exercises for the Text
I.
1.F
2.F
3.F
4.T
5.T
6.T
7.T
8.F
9.T 10.F
II.
1.attracts
2.leisure
3.available
4.limited
5.estimate
1.decided on
2.approved
3.estimate
4.carried over
5.put up with
6.characteristic of
IV.
1.B
2.C
3.B
4.A
5.C
6.D
Grammar Exercises
I.
1.SV
2.SVO
3.SVOC
4.SVC
5.SVO
6.SVOC
7.SVOC
8.SVO
9.SVOO 10.SVOC
11.SVOC 12.SVC 13.SVOC 14.SVOO 15.SVC
II.
1.prefer
2.insisted
3.need
4.make
5.remember
6.look
7.worked
8.was
9.sounds 10.gave
III.
1.B
2.C
3.D
4.A
5.B
6.C
7.A
8.D
9.A 10.D
IV.
1.The two languages are different/not similar in many way.
2.The deaf and dumb can neigher speak nor hear.
3.The Englishman speaks a very good Italian.
4.Could you pass me a cup of coffee.
5.At this time he felt thirsty and hungry.
6.Yesterday evening she asked me to wait for her at the gate of the restaurant.
7.When did you get up this morning.
8.The story sounds interesting,but it is not true.
9.The meat and macaroni cost me 25 yuan.
10.She oftern teaches the children to sing English songs.
Unit 3
Text A
Exercises for the Text
1.d
2.d
3.c
4.b
5.d
II.
1.long/wide
2.across
3.deep
4.around
5.high
III.
1.The,/,/
2.The
3.the,the
4./
5./,a
6./,the
7./ 8.The,the,the 9.The,the
10./
IV.
1.unwilling
2.avarage
3.take
4.runs
5.Suppose
V.
1.On the avarage there are 1,000 vistors a day.
2.The Atlantic Ocean is only as half as the Pacific,but it is moar than 4,000 miles wid
e.
https://www.360docs.net/doc/145428358.html,st night it took him a long time to get to sleep.
4.There are so many ads on TV that it is to remember how many there are.
5.Many wrong ideas about the Atlantic made the people in Columbus'days unwilling t o sail westward.
Vocabulary Exercises
I.
1.a.sailed b.sailor c.sail(n.)
2.a.willing b.unwillingly c.unwilling
3.a.unusual https://www.360docs.net/doc/145428358.html,ual https://www.360docs.net/doc/145428358.html,ually
4.a.average(n.) b.average(a.) c.averaged(v.)
II.
1.peak
2.crew
3.average
4.blils
5.unusual
6.highway
7.narrow 8.salty 9.spot
10.affected
III.
1.The sailors were afraid that might meet bad weather.
2.The mountain is half as high as Mount Tai.
3.On the average there are 45 students in every class of the school.
4.The climate affects the growth of plants.
5.My work keeps pilling up.
Text B
Exercises for the Text
I.
1.T
2.T
3.F
4.T
5.F
6.T
7.T
8.T
9.F 10.T
II.
1.three
2.the earth's gravitational pull.
3.it is near
4.29.5
5.its own/reflects
6.disc
7.the old moon in the new moon's arms.
8.outline
9.the old earth in the new earth's arms
10.night
Vocabulary Exercises
I.
1.d
2.b
3.a
4.c
5.e
II.
1.C
2.C
3.B
4.A
5.D
6.C
7.B
8.B
9.B 10.D
Grammar Exercises
I.
depend--dependence explain--explanation
form--formation conclude--conclusion inform--information move--movement mean--meaning govern--government graduate--graduation similar--aimilarity confuse--confusion pay--payment
agree--agreement advertise--advertisement announce--announcement add--addition
decide--decision use--usefulness
attract--attraction mix--mixture
II.
science--scientific sulless--sullessful response--responsible color--colorful
nation--national revolution--revolutionary addition--additional help--helpful
person--personal meaning--meaningful accept--acceptable use--useful
wood--wooden act--active
III.
disagree eimpractical independent uncover inexact incomplete disorder unhappy informal inpossible inactive uncertain discharge dishonest impolite
IV.
1.try n. 尝试；试验
经过许多次尝试后，他们终于取得了成功。
2.say n. 发言权
在所有的事务中妇女应享有平等的发言权。
3.market v.（在市场上）销售
三年后他们开始在市场上销售他们的产品。
4.journey v. 游历
要到那儿，他们得踏遍整个山区。
5.make n. 牌子；产品
虽然乍一看我们的产品比其它产品的价格要高，可顾客还是愿意买我们的产品。
6.parrot v. 鹦鹉学舌般地重复
老板说什么，他学说什么。
7.wine v. 喝酒
他们吃喝到深夜。
8.empty v. 使流入
这条小溪流入黄河。
9.head v. 作为...之首
后来他被任命为经理主管这个公司。
10.bridge v. 越过；跨过（障碍）
这项政策将有助于度过难关。
11.slow v. 使慢下来
火车减速一半。
12.after-sale a. 售后的
如果你们能提供令人满意的售后服务，你们的产品肯定会在这儿有市场。
13.machine v. 加工
机床是用来加工金属制品的。
14.take-off 起飞
飞机起飞时禁止吸烟。
15.radiocontrol 无线电控制
所有的模型飞机都是无线电遥控的。
16.downtown 城市商业区的
繁忙的商业街或购物中心通常是开饭店的好场所。
17.will 意志力；决心
有志者，事竟成。
18.house v. 给...房子住
据说这套新公寓能住下六口之家。
19.water v. 淌口水
见到苹果，他直流口水。
20.rule v. 控制；支配
有钱就有势。
Unit 4
Text A
Exercises for the Text
I.
1.c
2.b
3.b
4.d
5.c
II.
1.smooth
2.similar
3.mental
4.municipal
5.meaningful
https://www.360docs.net/doc/145428358.html,eful
7.familar 8.single 9.striking
10.difficult
III.
https://www.360docs.net/doc/145428358.html,rmation that does not make any sense to you is difficult to remember.
2.Association refers to associating what we want to remember with what we have alre ady remembered.
3.Catagorezing words helps memory.
4.Needless to say,if the books in the library were kept in a random order,readers coul
d not find th
e books they wanted.
5.Forming an integrated image with all the information placed in a single memtal pict ure can help up to preserve a memory.
Vocabulary Exercises
I.
1.a.psychologist b.psychology c.psychological
2.a.meaningless b.meaning c.meaningful
https://www.360docs.net/doc/145428358.html,anized https://www.360docs.net/doc/145428358.html,anizer https://www.360docs.net/doc/145428358.html,anization
4.a.repeated b.repetition c.repeat
II.
1.ability
2.accurately
3.focus
4.needless
5.meaningful
6.random
7.Repetition 8.preserve 9.improvement
10.image 11.related to 12.associate,with
III.
1.mean
https://www.360docs.net/doc/145428358.html,anize
3.visualize
4.associate
5.improve
6.repeat
7.memorize https://www.360docs.net/doc/145428358.html,municate 9.categorize
10.imagine
IV.
1.Their research focuses on the learning skills of adults.
2.It is meaningful to know how to use these phrases.
3.The adult group consists of 15 people.
4.Needless to say,we all know these facts.
5.Memory refers to the ability to remember the past events or experience.
6.I always associate the song with my school life.
Text B
Exercises for the Text
I.
1.T
2.F
3.T
4.F
5.T
6.F
7.F
8.F
9.F 10.T
II.
1.eighteen
2.repeat the number over and over
3.a cage an three doors
4.wait a short time
5.a random
6.reward
7.beginning,intermediate,advanced,and native-speaking students
8.Weather,whether,wither,wetter
9.recall,contrast,interrupt,dial
10.the meaning of words
Vocabulary Exercises
I.
1.e
2.b
3.a
4.c
5.d
II.
1.kept
2.contrast
3.human
4.released
5.intermediate
III.
1.C
2.D
3.A
4.D
5.B
Grammar Exercises
I.
1.declarative sentence
2.imperative sentence
3.declarative sentence
4.exclamatory sentence
5.interrogative sentence
6.exclamatory sentence
7.imperative sentence 8.declarative sentence
9.declarative sentence 10.imperative sentence
II.
1.Did he attend the English lecture yesterday?
2.Was it still raining when you came in?
3.Is there anyone in the house?
4.Was the baby well looked after?
5.Do you usually get up early in the morning?
6.Do you like to study in the reading room?
7.Can he tell you the result next week?
8.Was she able to swim across the lake?
9.Will it be good weather tomorrow?
10.Did Mr. Brown lose his job again?
III.
1.Where is the post office?
2.When did Tom graduate from college?
3.How does he study French?
4.Who lost the key to the door?
5.Why did Miss lee fell very bad?
6.What are listed in the telephone book?
7.How is your mother?
8.Which bus do you think she is going to take?
9.What did he advise you to go?
10.Why did he come?
IV.
1.She and husband disagree on many issues.
2.Cluld you talk about the problems about taxation.
3.Bring me a glass of water,please.
4.Your uncle does not say a word at home,does he?
5.What are the customers complaining about?
6.Did he travel in France of in Italy last summer?
7.Did you read the ad in a newspaper or in a magazine?
8.Do you have to pay a sales tax when you buy something?
9.Who is responsible for the company's advertising?
10.Many salaried people did not support the federal goverment at that time,did they? Unit 5
Text A
Exercises for the Text
I.
1.b
2.d
3.d
4.c
5.c
II.
1.bravery
2.eager
3.civilized
4.overseas
5.substitute
6.foundation
7.mixture 8.belief 9.protein
10.contain
III.
1.pianos/violins
2.firemen
3.data
4.deer
5.potatoes/tomatoes
IV.
1.The soldiers ate millions of pounds of potatoes during WWII.
2.One wrong idea was that by eating an animal people could get some of the good qua lities of that animal for themselves.
3.It has not yet been proved whether fish is the best brain food.
https://www.360docs.net/doc/145428358.html,k contains rich protein.Therefore,many people drink it for breakfast.
5.Today many people have wrong ideas about food
Vocabulary Exercises
I.
1.a.civilize b.civilized c.civilization
2.a.free b.freedom c.freely
3.a.digest b.digestible c.digestion d.digestive
4.a.scientists b.scientific c.science
II.
1.mixture
2.poisonous
3.suppose
4.digest
5.widespread
6.overseas
7.similar 8.foundation 9.eager
10.substitute
III.
1.digestion
2.mixture
3.belief
4.civilization
https://www.360docs.net/doc/145428358.html,bination
IV.
1.We have not found a substitute for him.
2.children are eager to become as strong and brave as the heroes in the movies.
3.He is supposed to run fastest among us.
4.Some stories are widespread,while others are not.
5.As a matterof fact,meat and potatoes can be eaten at the same meal.
6.School are often thought of as a small society.
Text B
Exercises for the Text
I.
1.T
2.F
3.T
4.F
5.T
6.T
7.T
8.T
9.T 10.T
II.
1.true
2.run races / wrestle / have mock fights together
3.Frogs / owls
4.sport / very grave
5.their dams and their houses
6.take care of sheep
7.find new ways
8.new fashions / none from each other
9.methods
10.instinct
11.ant / frog / owl / beaver / parrot / horse / dog /elephant / sheep / spider Vocabulary Exercises
I.
1.d
2.c
3.b
4.a
5.e
II.
1.D
2.A
3.C
4.D
5.D
6.D
7.A
8.B
9.B 10.C
Grammar Exercises
I.
Simple sentences are 8,10.
Compound sentences are 2,4,6,7,9.
complex sentences are 1,3,5.
II.
1.B
2.D
3.D
4.C
5.B
6.A
7.C
8.C
9.D 10.A
Unit 6
Text A
Exercises for the Text
I.
1.b
2.a
3.b
4.c
5.c
II.
1.rare
2.substance
3.slight
4.pressure
5.crystal
6.crack
7.gem 8.elevator 9.crush
III.
1.It was thought that the earth was flat.
2.It is reported that a new government has been formed.
3.It was believed that the sun traveled around the earth.
4.It is believed that living things exist on Mars.
5.It is said that the world temperature is growing higher.
IV.
1.stick to
2.change...into
3.stick to
4.running out
5.pick up
6.changed into
7.had run out 8.picked up 9.sorting out
10.sort out
V.
1.It is known to all that diamonds are the hardest substance.
2.Today most diamonds are not found in stream beds but mined from rock formation s deep inside the earth.
3.Diamonds,as they are mined,do not look very expressive.
4.He never sticks to anything he does.
5.The eruption of active vocanoes is a terrible natural phenomenon.
Vocabulary Exercises
I.
1.a.popularity b.popularize c.popular
2.a.hand b.hand c.handful
3.a.formed b.formation c.forms
4.a.impression b.impressive c.impressed
II.
1.experienced
2.Extreme
3.formation
4.pressure
5.blasted
6.handful
7.crystal 8.destroyed 9.unusual
10.flow
III.
1.Please sort out what you want and throw away the rest.
2.The price of the elevator is somewhat higher than expected.
3.These designs are very popular with young people.
4.He stopped writing because his pen had run out of ink.
5.Experienced people can tell which one is real immediately. Text B
Exercises for the Text
I.
1.F
2.T
3.F
4.F
5.F
6.T
7.F
8.T
9.T 10.T
II.
1.difficulty
2.haze
3.magnifying glass
4.do/be
5.guessing
6.vegetable
https://www.360docs.net/doc/145428358.html,e first/a higher order of beings 8.earth/air
9.flowers/fruits/grain 10.dissolves
Vocabulary Exercises
I.
1.d
2.b
3.a
4.c
5.e
II.
1.puzzled
2.dissolve
3.aside
4.magnifying
https://www.360docs.net/doc/145428358.html,tter
6.observes
7.beneath 8.broad
Grammar Exercises
I.
1.died
汤姆父亲去世时他23岁。
2.does not guarantee
仅仅练习并不能保证成年语言学习者的成功。
3.advised
他建议他儿子到30岁再结婚。
4.is looking
她正找机会同他谈一谈。
https://www.360docs.net/doc/145428358.html,es
等着轮到你。
6.was going
他正要离开饭店，这时经理进来了。
7.will have left
快点！否则，我们到火车站时火车就要开走了。
8.would help
她说第二天将帮助丈夫洗车。
9.will be sitting
明天的这个时候他们将在看电影。
10.were playing
这些男孩透过窗户往外看，看见一些小象在外面玩耍。
11.will go
一百年之后，人们将会到其它的星球上度假。
12.had finished
他吃完早饭后，就到售票处去了。
13.would be
她终于认识到考虑一下出国的费用是明智的。
14.will have locked
快点！否则你还没进去，商店就关门了。
15.had been getting
他认为最近天气一直很好。
16.had benn keeping
我只想让你知道你使我们一直没睡着。
17.had happened
差不多一个星期过去了，那个女孩才能解释发生的一切。18.will tell
当你问他时，她就会把这个消息告诉你。
19.had finished
我还没有吃完早饭，约翰就打电话来说要来看我。
20.has passed/failed
乔治通过了驾驶考试，可没有通过学校考试。
II.
1.B
2.B
3.D
4.D
5.B
6.B
7.D
8.A
9.D 10.A
III.
1.invented
2.offer
3.have been setting
4.brought
5.has not paid
6.had seen
7.was making 8.has been working 9.am preparing
10.has happened
IV.
1.Students from a medical institute are now observing an operation.
2.Wind blows hard in March.
3.Where are you going to hang that photo?
4.She fell down when she was going downstairs.
5.How many years has Henry learned cooking from Miss Smith?
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新视野大学英语读写教程第二版第二册课后练习答案 unit 1 Section A: Vocabulary III. 1. charge 2. convention 3. efficient 4. obtain 5. competent 6. asessing 7. fulfill 8. conducting 9. consequently 10. significance IV. 1. behind 2. at 3. in 4.out 5. to 6. to 7.in 8.with 9.but 10. for V. 1. L 2. C 3.D 4. N 5. O 6.A 7. E 8.G 9.I 10. K Word Building VI. https://www.360docs.net/doc/145428358.html,mitment 2. attraction 3. appointment 4.impression 5. civilization https://www.360docs.net/doc/145428358.html,position 7.confusion 8.congratulation 9.consideration 10.explanation 11. acquisition 12.depression VII. 1.advisable 2.disirable 3.favorable 4. considerable 5. remarkable 6.preferable 7.drinkable 8.acceptable Sentence Structure VIII. 1.much less can he write English articles 2.much less can he manage a big company 3.much less could he carry it upstairs 4.much less have I spoken to him 5.much less to read a lot outside of it IX. 1.Having meals at home can cost as little as two or three dollars, whereas eating out at a restaurant is always more expensive. 2.We thought she was rather proud,whereas in fact she was just very shy. 3.We have never done anything for them, whereas they have done so much for us. 4.Natalie prefers to stay for another week, whereas her husband prefers to leave immediately. 5.Some praise him highly,whereas others put him down severely. Translation X. 1.She wouldn't take a drink, much less could she stay for dinner. 2.He thought I was lying to him,whereas I was telling the truth. 3.How do you account for the fact that you have been late every day this week?
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第3章处理机调度1）选择题 （1）在分时操作系统中，进程调度经常采用_D_ 算法。 A. 先来先服务 B. 最高优先权 C. 随机 D. 时间片轮转 （2）_B__ 优先权是在创建进程时确定的，确定之后在整个进程运行期间不再改变。 A. 作业 B. 静态 C. 动态 D. 资源 （3）__A___ 是作业存在的惟一标志。 A. 作业控制块 B. 作业名 C. 进程控制块 D. 进程名 （4）设有四个作业同时到达，每个作业的执行时间均为2小时，它们在一台处理器上按单道方式运行，则平均周转时间为_ B_ 。 A. l小时 B. 5小时 C. 2.5小时 D. 8小时 （5）现有3个同时到达的作业J1、J2和J3，它们的执行时间分别是T1、T2和T3，且T1＜T2＜T3。系统按单道方式运行且采用短作业优先算法，则平均周转时间是_C_ 。 A. T1+T2+T3 B. (T1+T2+T3)/3 C. (3T1+2T2+T3)/3 D. (T1+2T2+3T3)/3 （6）__D__ 是指从作业提交给系统到作业完成的时间间隔。 A. 运行时间 B. 响应时间 C. 等待时间 D. 周转时间 （7）下述作业调度算法中，_ C_调度算法与作业的估计运行时间有关。 A. 先来先服务 B. 多级队列 C. 短作业优先 D. 时间片轮转 2）填空题 （1）进程的调度方式有两种，一种是抢占(剥夺)式，另一种是非抢占(非剥夺)式。 （2）在_FCFS_ 调度算法中，按照进程进入就绪队列的先后次序来分配处理机。 （3）采用时间片轮转法时，时间片过大，就会使轮转法转化为FCFS_ 调度算法。 （4）一个作业可以分成若干顺序处理的加工步骤，每个加工步骤称为一个_作业步_ 。 （5）作业生存期共经历四个状态，它们是提交、后备、运行和完成。 （6）既考虑作业等待时间，又考虑作业执行时间的调度算法是_高响应比优先____ 。 3）解答题 （1）单道批处理系统中有4个作业，其有关情况如表3-9所示。在采用响应比高者优先调度算法时分别计算其平均周转时间T和平均带权周转时间W。（运行时间为小时，按十进制计算） 表3-9 作业的提交时间和运行时间
大学英语课后习题答案解析
U n i t1V o c a b u l a r y1： 1、My job varies between the extremely tedious and the annoyingly busy. On balance I think I'm happier during the really busy times; no time to think about how bored I am。 我的工作既有特无聊的时候，也有忙得要命的时候。但总的来说，我在真正忙的时候高兴些，因为在那个时候，我没时间去想我有多厌倦。 2、It is the nature of the wise to resist leasures, but the foolish to be a slave to them。 明智之人天生会抵制享乐，而愚蠢之人却成了它的奴隶。 3、I figure out a good team of dogs, hitched to a light sled, can haul 1,000 pounds of goods. 一组健壮的狗可以用轻小的雪橇拉动1,000磅的货物。 4、In the story, the little girl has a wicked stepmother, who makes her life a misery. 在这个故事中，小女孩有一个心肠很坏的继母，让她生活很痛苦。 5、Nothing ever becomes real till it is experienced -- even a proverb is no proverb to you till your life has illustrated it. 眼见为实——即使是谚语在你没有在生活中得到证明时，也不一定正确。 6、Nowadays almost all libraries are finding it increasingly difficult to remain within Their budget. 当前，几乎所有图书馆发现靠他们的预算生存下去越来越难。 7、You can increase a tyre’s grip in winter by slightly lowering its pressure . 冬天可以稍微放点气来增强轮胎的抓力。 8、Lakes Superior, Huron, Erie, and Ontario are shared by the United States and Canada, and form part of the boundary between the two countries. 苏比利尔湖、修伦湖、伊利湖和安大略湖归美国和加拿大共同所有，也构成了两国的部分分界线。 9、The police are investigating the three men allegedly involved in organizing and carrying out the bank robbery. 警方正在调查这三名涉嫌参与组织和实施银行抢劫案的人。 10、I do not doubt in the least that inflation leads to economic decline. 我毫不怀疑，通货膨胀导致经济衰退。 11、A blizzard was blasting great drifts of snow across the lake.（吹起） 暴风雪席卷了整个湖面。 12、Tim says just about everybody will be affected by the tax increase, but I’m sure he’s exaggerating. （几乎） 蒂姆说，几乎每个人都会受到增税的影响，但我肯定他是在夸大其词。 Vocabulary 2 : an effort to feel better , I started to make small changes in my life and cut down /back from 20 cigarettes in day to a mere three or four. 为了感觉更好，我开始做一些小小的改变在我的生活中，以及减少从每天20支香烟到大约只有三或四。 I wasted electricity as you do at home , my dad would make me pick up the bill. 如果我像你一样浪费在家浪费电的话，我的爸爸将肯定会让我支付账单（自己买单）。 can get by with four computers at the moment , but we’ll need a couple more when the new staff arrive.
操作系统课后题答案
2.1 一类操作系统服务提供对用户很有用的函数，主要包括用户界面、程序执行、I/O操作、文件系统操作、通信、错误检测等。 另一类操作系统函数不是帮助用户而是确保系统本身高效运行，包括资源分配、统计、保护和安全等。 这两类服务的区别在于服务的对象不同，一类是针对用户，另一类是针对系统本身。 2.6 优点：采用同样的系统调用界面，可以使用户的程序代码用相同的方式被写入设备和文件，利于用户程序的开发。还利于设备驱动程序代码，可以支持规范定义的API。 缺点：系统调用为所需要的服务提供最小的系统接口来实现所需要的功能，由于设备和文件读写速度不同，若是同一接口的话可能会处理不过来。 2.9 策略决定做什么，机制决定如何做。他们两个的区分对于灵活性来说很重要。策略可能会随时间或位置而有所改变。在最坏的情况下，每次策略改变都可能需要底层机制的改变。系统更需要通用机制，这样策略的改变只需要重定义一些系统参数，而不需要改变机制，提高了系统灵活性。 3.1、短期调度：从准备执行的进程中选择进程，并为之分配CPU； 中期调度：在分时系统中使用，进程能从内存中移出，之后，进程能被重新调入内存，并从中断处继续执行，采用了交换的方案。 长期调度：从缓冲池中选择进程，并装入内存以准备执行。 它们的主要区别是它们执行的频率。短期调度必须频繁地为CPU选择新进程，而长期调度程序执行地并不频繁，只有当进程离开系统后，才可能需要调度长期调度程序。 3.4、当控制返回到父进程时，value值不变，A行将输出：PARENT：value=5。 4.1、对于顺序结构的程序来说，单线程要比多线程的功能好，比如（1）输入三角形的三边长，求三角形面积；（2）从键盘输入一个大写字母，将它改为小写字母输出。
全新版大学英语第一册课后练习答案
全新版大学英语第一册课后练习答案 unit 5 [转贴 2007-05-21 08:38:38] 字号：大 中 小 Text Organization 1. 1) Para 2 His interest in her had begun twelve months before in a Florida library. 2) para 7 I will let Mr.Blanchard tell you what happened. 3) prar16 It is not difficult to understand and admire Miss Maynell’s wisdom. 2. Parts Paragraphs Main Idea Part Two Paras2—6 How John Blanchard had fallen in love with Miss Maynell Part Three Paras7--15 Miss Maynell put Blanchard to a test Part Four Paras16--17 It was wise of Miss Maynell to give such a test 、管路敷设技术通过管线敷设技术，不仅可以解决吊顶层配置不规范问题，而且可保障各类管路习题到位。在管路敷设过程中，要加强看护关于管路高中资料试卷连接管口处理高中资料试卷弯扁度固定盒位置保护层防腐跨接地线弯曲半径标高等，要求技术交底。管线敷设技术中包含线槽、管架等多项方式，为解决高中语文电气课件中管壁薄、接口不严等问题，合理利用管线敷设技术。线缆敷设原则：在分线盒处，当不同电压回路交叉时，应采用金属隔板进行隔开处理；同一线槽内，强电回路须同时切断习题电源，线缆敷设完毕，要进行检查和检测处理。、电气课件中调试对全部高中资料试卷电气设备，在安装过程中以及安装结束后进行高中资料试卷调整试验；通电检查所有设备高中资料试卷相互作用与相互关系，根据生产工艺高中资料试卷要求，对电气设备进行空载与带负荷下高中资料试卷调控试验；对设备进行调整使其在正常工况下与过度工作下都可以正常工作；对于继电保护进行整核对定值，审核与校对图纸，编写复杂设备与装置高中资料试卷调试方案，编写重要设备高中资料试卷试验方案以及系统启动方案；对整套启动过程中高中资料试卷电气设备进行调试工作并且进行过关运行高中资料试卷技术指导。对于调试过程中高中资料试卷技术问题，作为调试人员，需要在事前掌握图纸资料、设备制造厂家出具高中资料试卷试验报告与相关技术资料，并且了解现场设备高中资料试卷布置情况与有关高中资料试卷电气系统接线等情况，然后根据规范与规程规定，制定设备调试高中资料试卷方案。、电气设备调试高中资料试卷技术电力保护装置调试技术，电力保护高中资料试卷配置技术是指机组在进行继电保护高中资料试卷总体配置时，需要在最大限度内来确保机组高中资料试卷安全，并且尽可能地缩小故障高中资料试卷破坏范围，或者对某些异常高中资料试卷工况进行自动处理，尤其要避免错误高中资料试卷保护装置动作，并且拒绝动作，来避免不必要高中资料试卷突然停机。因此，电力高中资料试卷保护装置调试技术，要求电力保护装置做到准确灵活。对于差动保护装置高中资料试卷调试技术是指发电机一变压器组在发生内部故障时，需要进行外部电源高中资料试卷切除从而采用高中资料试卷主要保护装置。
操作系统概念课后习题答案整理.doc
1.1在多道程序和分时环境中，多个用户同时共享一个系统，返种情冴导致多种安全问题。a. 列出此类的问题b.在一个分时机器中，能否确保像在与用机器上一样的安全度？并解释乀。 Answer:a.窃叏戒者复制某用户癿程序戒数据；没有合理癿预算来使用资源（CPU，内存，磁盘空闱，外围设备）ｂ．应该丌行，因为人类设计癿仸何保护机制都会丌可避兊癿被另外癿人所破译，而丏径自信癿认为程序本身癿实现是正确癿是一件困难癿亊。 1.2资源的利用问题在各种各样的操作系统中出现。试例丼在下列的环境中哪种资源必须被严栺的管理。（ａ）大型电脑戒迷你电脑系统（ｂ）不服务器相联的工作站（ｃ）手持电脑 Answer: （ａ）大型电脑戒迷你电脑系统：内存呾CPU资源，外存，网络带宽（ｂ）不服务器相联癿工作站：内存呾CPU资源（ｃ）手持电脑：功率消耗，内存资源 1.3在什举情冴下一个用户使用一个分时系统比使用一台个人计算机戒单用户 工作站更好？ Answer:当另外使用分时系统癿用户较少时，仸务十分巨大，硬件速度径快，分时系统有意丿。充分利用该系统可以对用户癿问题产生影响。比起个人电脑，问题可以被更快癿解决。迓有一种可能収生癿情冴是在同一时闱有许多另外癿用户在同一时闱使用资源。当作业足够小，丏能在个人计算机上合理癿运行时，以及当个人计算机癿性能能够充分癿运行程序来达到用户癿满意时，个人计算机是最好癿，。 1.4在下面丼出的三个功能中，哪个功能在下列两种环境下，(a)手持装置(b)实
时系统需要操作系统的支持？(a)批处理程序(b)虚拟存储器(c)分时 Answer:对二实时系统来说，操作系统需要以一种公平癿方式支持虚拟存储器呾分时系统。对二手持系统，操作系统需要提供虚拟存储器，但是丌需要提供分时系统。批处理程序在两种环境中都是非必需癿。 1.5描述对称多处理（ＳＭＰ）和非对称多处理乀间的区别。多处理系统的三个优点和一个缺点？ Answer:ＳＭＰ意味着所以处理器都对等，而丏I/O可以在仸何处理器上运行。非对称多处理有一个主处理器控制系统，不剩下癿处理器是随从关系。主处理器为从处理器安排工作，而丏I/O也叧在主处理器上运行。多处理器系统能比单处理器系统节省资金，返是因为他们能共享外设，大容量存储呾电源供给。它们可以更快速癿运行程序呾增加可靠性。多处理器系统能比单处理器系统在软、硬件上也更复杂（增加计算量、觃模经济、增加可靠性） 1.6集群系统不多道程序系统的区别是什举？两台机器属二一个集群来协作提 供一个高可靠性的服务器的要求是什举？ Answer:集群系统是由多个计算机耦合成单一系统幵分布二整个集群来完成计算仸务。另一方面，多道程序系统可以被看做是一个有多个CPU组成癿单一癿物理实体。集群系统癿耦合度比多道程序系统癿要低。集群系统通过消息迕行通信，而多道程序系统是通过共享癿存储空闱。为了两台处理器提供较高癿可靠性服务，两台机器上癿状态必项被复制，幵丏要持续癿更新。当一台处理器出现敀障时，另一台处理器能够接管敀障处理癿功能。 1.7试区分分布式系统（distribute system）的客户机-服务器（client-server）模型不对等系统（peer-to-peer）模型