高三第一次周练

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高三上期元月第一次周练文科数学试卷

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三、解答题
18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
12. 已知椭圆 + ＝1（a＞b＞0）的离心率
，连接椭圆的四个顶点得到的菱形的面积为 4．
（Ⅰ）求椭圆的方程；（Ⅱ）设过点 A（﹣a，0）的直线 l 与椭圆相交另一点 B，若
，求直线 l 的倾斜角．
高三上期元月第一次周练文科数学试卷
一、单选题
1234567 [A] [A] [A] [A] [A] [A] [A] [B] [B] [B] [B] [B] [B] [B] [C] [C] [C] [C] [C] [C] [C] [D] [D] [D] [D] [D] [D] [D]
1. 以椭圆 C：
1
二、填空题
8
9
10
11
8. 方程
表示焦点在 x 轴上的椭圆，则实数 k 的取值近线的双曲线经过点（4，1），则该双曲线的标准方程为
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10. 斜率为的直线过抛物线 C：y2＝4x 的焦点，且与 C 交于 A，B 两点，则|AB|＝
．
11. 双曲线
的一条渐近线方程为 y＝2x，且焦点到渐近线的距离为 2，则双曲线的方程为
（
）
A．1
B．7
C．9
D．7 或 9
4. 已知椭圆 + ＝1 左、右焦点分别为 F1、F2，点 P 在椭圆上．若 PF1⊥PF2，则 P 到 x 轴的距离为（）
A．
B．3
C．
D．
5. 已知 A 为抛物线 C：y2＝2px（p＞0）上一点，点 A 到 C 的焦点的距离为 12，到 y 轴距离为 9，则 p＝（）
A．2

高三9月第一周练考(地理)试题含答案

高三9月第一周练考（地理）（考试总分：100 分）一、选择题组（本题共计13小题，总分45分）1.（4.5分）夏威夷群岛中的毛伊岛和希腊的锡拉岛(如图所示)上有世界闻名的红沙滩。

读图，完成1～3题。

1．毛伊岛位于锡拉岛的( )A．西北方向 B．东南方向 C．正北方向 D．正南方向2．从毛伊岛到锡拉岛的最短航线的航向是( )A．一直向西北B．一直向东C．先向北，后向南D．先向南，后向北3．两岛间最短距离约为( )A．7 000 km B．11 000 km C．13 600 km D．16 000 km2.（3分）2019年2月19日,我国在塔里木盆地顺北油气田完成某钻井钻探,钻井深8 588米,创亚洲陆上钻井最深纪录。

据此回答1-2题:1．该钻井( )A.未穿透地壳B.深达莫霍界面C.已穿透岩石圈D.即将穿透地幔2．该钻井深达8 500多米表明当地拥有深厚的( )A.侵入岩B.喷出岩C.变质岩D.沉积岩3.（4.5分）2019年春节热映的《流浪地球》讲述了地球因太阳“氦闪”而被迫逃离太阳系寻找新家园的故事。

“流浪地球”计划分为三步：第一步中止地球自转:人们利用地球发动机反向喷射使地球停止自转。

第二步，将地球推入土星轨道，借助土星引力，弹射出太阳系。

第三步，地球经历2 500年的星际流浪，抵达新家园。

下图为地球流浪过程示意图。

据此回答1-3题。

1．如果地球停止自转，可能出现的地理现象是( )A．地球上没有时间差异 B．地球各地的温度将保持不变C．地球的昼夜现象消失 D．海水向两极移动淹没大量陆地2．如果地球搬家的第一步成功，地球上存在生命的条件将被严重影响的是( ) A．安全的宇宙环境 B适宜的温度范围C．适中的日地距离 D．稳定的太阳光照3．地球抵达新家园，所处的天体系统是( )A．地月系 B．太阳系 C．河外星系 D．银河系4.（3分）云量是以一日内云遮蔽天空的百分比来表示。

下图示意我国某地区多年平均云量日均值分布。

高三数学周练(一)

40m x 40m 高三数学周练（一）一．选择题：1.（2010湖南文数）2. 下列命题中的假命题．．．是 A. ,lg 0x R x ∃∈= B. ,tan 1x R x ∃∈= C. 3,0x R x ∀∈> D. ,20x x R ∀∈>2.（2010湖北理数）2．设集合()22{,|1}416x y A x y =+=，{(,)|3}x B x y y ==，则A B ⋂的子集的个数是A ．4B ．3C ．2D ．13.（2013年高考江西卷（理））函数y=x ln(1-x)的定义域为A.(0,1)B.[0,1)C.(0,1]D.[0,1]4.（2013年高考新课标1（理））已知函数()f x =22,0ln(1),0x x x x x ⎧-+≤⎨+>⎩,若|()f x |≥ax ,则a 的取值范围是A.(,0]-∞B.(,1]-∞C.[2,1]-D.[2,0]-5.（2013年高考陕西卷（理））在如图所示的锐角三角形空地中, 欲建一个面积不小于300m 2的内接矩形花园(阴影部分), 则其边长x (单位m )的取值范围是(A) [15,20] (B) [12,25] (C) [10,30] (D) [20,30]6.（2012年高考（浙江理））把函数y =cos2x +1的图像上所有点的横坐标伸长到原来的2倍(纵坐标不变),然后向左平移1个单位长度,再向下平移1个单位长度,得到的图像是7.（2012年高考（新课标理））已知{}n a 为等比数列,472a a +=,568a a =-,则110a a += （） A ．7B ．5C ．-5D ．-7二．填空题： 8.（ 2012年高考（江苏））设α为锐角,若4cos 65απ⎛⎫+= ⎪⎝⎭,则)122sin(π+a 的值为____. 9.（2012年高考（新课标理））数列{}n a 满足1(1)21n n n a a n ++-=-,则{}n a 的前60项和为_______10.（2010重庆理数）已知函数()f x 满足：()114f =，()()()()()4,f x f y f x y f x y x y R =++-∈，则()2010f =_____________.三。

2024学年广东省越秀外国语学校高三4月第一次周练物理试题

2024学年广东省越秀外国语学校高三4月第一次周练物理试题请考生注意：1．请用2B铅笔将选择题答案涂填在答题纸相应位置上，请用0．5毫米及以上黑色字迹的钢笔或签字笔将主观题的答案写在答题纸相应的答题区内。

写在试题卷、草稿纸上均无效。

2．答题前，认真阅读答题纸上的《注意事项》，按规定答题。

一、单项选择题：本题共6小题，每小题4分，共24分。

在每小题给出的四个选项中，只有一项是符合题目要求的。

1、如图所示，某竖直弹射装置由两根劲度系数为k 的轻弹簧以及质量不计的底盘构成，当质量为m 的物体竖直射向空中时，底盘对物体的支持力为6mg(g 为重力加速度)，已知两根弹簧与竖直方向的夹角为θ＝60°，则此时每根弹簧的伸长量为A．B．C．D．2、木星和土星都拥有众多的卫星，其中“木卫三”作为太阳系唯一一颗拥有磁场的卫星，在其厚厚的冰层下面可能存在生命，而“土卫二”具有生命诞生所需的全部要素，是最适宜人类居住的星球，经探测它们分别绕木星和土星做圆周运动的轨道半径之比为a，若木星和土星的质量之比为b，则下列关于“木卫三”和“土卫二”的相关说法正确的是（）A．运行周期之比为3abB．向心加速度之比为baC．环绕速度之比为abD．表面重力加速度之比2ba3、如图甲所示，理想变压器原、副线圈的匝数比为2∶1，电阻55Ω，电流表、电压表均为理想电表。

原线圈A、B 端接入如图乙所示的正弦交流电压，下列说法正确的是A．电流表的示数为4.0AB．电压表的示数为155.6VC．副线圈中交流电的频率为50HzD．穿过原、副线圈磁通量的变化率之比为2∶14、火箭向后喷气后自身获得向前的速度。

某一火箭在喷气前的质量为30kg，间断性完成了多次向后喷气，每秒钟可完成5次喷气。

设每一次喷气均喷出200g气体，气体喷出后的速度为100m/s，则第三次喷气后火箭的速度为（题中涉及各速度均以地面为参考系）（）A．1000m/s B．200m/s C．20m/s D．2m/s5、如图所示，一光滑小球与一过球心的轻杆连接，置于一斜面上静止，轻杆通过光滑铰链与竖直墙壁连接，已知小球所受重力为G，斜面与水平地面的夹角为60°，轻杆与竖直墙壁的夹角也为60°，则轻杆和斜面受到球的作用力大小分别为（）A．G和G B．12G和32GC．32G和12G D．3G和2G6、如图所示为氢原子能级图，下列说法正确的是（）A．氢原子由较高能级跃迁到较低能级时，电势能减小，其核外电子的动能增大B．氢原子从n=2能级向n=1能级跃迁时辐射出的光子能量为17eVC．一群处于n=4能级的氢原子向低能级跃迁时，辐射出的光子频率最多有3种D．用能量为9eV和4.6eV的两种光子同时照射大量的氢原子，有可能使处于基态的氢原子电离二、多项选择题：本题共4小题，每小题5分，共20分。

2019-2020年高三上学期第一次周练数学试题含答案

2019-2020年高三上学期第一次周练数学试题含答案一、选择题，每小题只有一项是正确的。

1.满足条件的所有集合的个数是A.1B.2C. 3D. 42.下列说法正确的是（）A. 命题“使得 ”的否定是：“”B. “”是“)1,0(log )(≠>=a a x x f a 在上为增函数”的充要条件C. “为真命题”是“为真命题”的必要不充分条件D. 命题p ：“2cos sin ,≤+∈∀x x R x ”，则p 是真命题3.设函数，则下列关于函数的说法中正确的是（）A. 是偶函数B. 最小正周期为πxk|b|1C. 图象关于点对称D. 在区间上是增函数4.实数5lg 24lg 81log 22723log 322++∙- 的值为（）5.函数()sin ,[,],22f x x x x =∈-，则下列不等式一定成立的是( ) A ． B ．C ．D ．6.已知等比数列的首项公比，则 =+++1122212log log log a a a ( )A. 55B. 35C. 50D. 467.在等差数列中，，其前n 项和为的值等于A. B. C. D.8.在△ ABC 中，角 A 、B 、C 的对边分别为 a 、b 、c ，如果 cos(2)2sin sin 0B C A B ++<，那么三边长a 、b 、c 之间满足的关系是（）A ．B ．C ．D ．9.若点为圆的弦的中点，则弦所在直线方程为（）A ．B ．C ．D ．二、填空题10.已知复数 ()的模为,则的最大值是 .11.一根绳子长为米，绳上有个节点将绳子等分，现从个节点中随机选一个将绳子剪断，则所得的两段绳长均不小于米的概率为．12.曲线在点（1,－1）处的切线方程是______________.13.已知函数，关于的方程（）恰有6个不同实数解，则的取值范围是 .三、计算题14.（本小题满分14分）设对于任意的实数，函数，满足，且，，（Ⅰ）求数列和的通项公式；（Ⅱ）设，求数列的前项和（Ⅲ）已知，设，是否存在整数和。

高三数学上学期周周练试卷-函数3(附答案)

高三数学练习卷——函数（3）一、填空题（每小题5分，满分70分） 1. 函数xx f -=11)(的定义域为M ，)1ln()(x x g +=的定义域为N ，则=N M ▲ ． 2.命题“若12<x ，则11<<-x ”的逆否命题是 ▲ ． 3.已知集合)0,(-∞=A ，],2[a B -=，若A B A =，则实数a 的取值范围是 ▲ ．4.若不等式102x m x m -+<-成立的一个充分非必要条件是1132x <<，则实数m 的取值范围是 ▲ ． 5.方程02391=+-+x x的两根之和是 ▲ ．6. 已知函数b ax ax x g ++-=12)(2(0>a )在区间]3,2[上有最大值4和最小值1，则b a +的值为▲ ．7.已知72p =，75q =，则lg2用,p q 表示为 ▲ ．8.已知2123()(2,)n n f x x n k k Z -++==∈的图像在[0,)+∞上单调递增，则不等式2()(3)f x x f x ->+的解集为▲ ．9.已知函数f(x)= 22,0,3,0x ax x bx x x ⎧+≥⎪⎨-<⎪⎩为奇函数，则不等式f(x)<4的解集为 ▲ ． 10.已知函数b a x a b x x f ++--+=)2()(22是偶函数，则此函数图象与y 轴交点的纵坐标的最大值是▲ ．11. 设实数1≥a ，使得不等式a ax x ≥+-23，对任意的实数[]2,1∈x 恒成立，则满足条件的实数a 的范围是 ▲ ．12. 定义在R 上的函数f (x )的图象关于点（43-，0）对称，且满足f (x )= -f (x +23)，f (1)=1，f (0)=-2，则f (1)+f (2)+f (3)+…+f (2015)的值为 ▲ ．13.函数22()(1)(1)x axf x x x +=+-是奇函数的充要条件是a = ▲ ．14. 已知函数()()(1,1)1xf x x x=∈--，下列结论中正确结论的序号为 ▲ ．（1）(1,1)x ∀∈-，等式()()0f x f x -+=恒成立；（2）[)0,m ∀∈+∞，方程()f x m =有两个不等实数根；（3）()12,1,1x x ∀∈-，若12x x ≠，则一定有12()()f x f x ≠；（4）存在无数多个实数k ，使得函数()()g x f x kx =-在(1,1)-上有三个零点高三数学练习卷——函数（3）答卷班级姓名学号成绩一、填空题（每小题5分，满分70分）1. 2. 3. 4. 5. 6. 7. 8. 9. 10.11.12.13.14.二、解答题（本大题共6小题，共计90分，解答时应写出文字说明、证明或演算步骤） 15.(本小题满分14分)已知函数()sin()4f x A x π=+，x ∈R ，且53()122f π=.(1)求A 的值； (2)若3()()2f f θθ+-=，θ∈⎝ ⎛⎭⎪⎫0，π2，求3()4f πθ-.16． (本小题满分14分)已知函数f (x )＝sin(x ＋θ)＋a cos(x ＋2θ)，其中a ∈R ，θ∈⎝⎛⎭⎫－π2，π2. (1)当a ＝2，θ＝π4时，求f (x )在区间[0，π]上的最大值与最小值；(2)若f ⎝⎛⎭⎫π2＝0，f (π)＝1，求a ，θ的值．17. (本小题满分14分) 某实验室一天的温度(单位：℃)随时间t (单位：h)的变化近似满足函数关系：f (t )＝10－3cos π12t －sin π12t ，t ∈[0，24)．(1)求实验室这一天的最大温差．(2)若要求实验室温度不高于11℃，则在哪段时间实验室需要降温？18. (本小题满分16分) 已知函数1)(2-=x x f ，|1|)(-=x a x g ．（1）若R x ∈时，不等式)()(x g x f ≥恒成立，求实数a 的取值范围；（2）求函数()()()h x f x g x =+在区间[-2,2]上的最大值．19. (本小题满分16分) 已知函数22()(,,)xx f x aebe cx a b c R -=--∈的导函数()f x '为偶函数，且曲线()y f x =在点(0，f (0))处的切线的斜率为4－c .(1)确定,a b 的值；(2)若c ＝3，判断f (x )的单调性； (3)若f (x )有极值，求c 的取值范围．20. (本小题满分16分) 设函数()(,,)nn f x x bx cn N b c R +=++∈∈（1）设2n ≥，1,1b c ==-，证明：()n f x 在区间1,12⎛⎫⎪⎝⎭内存在唯一的零点；（2）设2n =，若对任意12,x x [1,1]∈-，有2122|()()|4f x f x -≤，求b 的取值范围；（3）在（1）的条件下，设n x 是()n f x 在1,12⎛⎫⎪⎝⎭内的零点，判断数列23,,,nx x x 的增减性.高三数学练习卷——函数（3）一、填空题（每小题5分，满分70分） 1. 函数xx f -=11)(的定义域为M ，)1ln()(x x g +=的定义域为N ，则=N M ▲ ． 2.命题“若12<x ，则11<<-x ”的逆否命题是 ▲ ． 3.已知集合)0,(-∞=A ，],2[a B -=，若A B A =，则实数a 的取值范围是 ▲ ．4.若不等式102x m x m -+<-成立的一个充分非必要条件是1132x <<，则实数m 的取值范围是 ▲ ． 5.方程02391=+-+x x的两根之和是 ▲ ．6. 已知函数b ax ax x g ++-=12)(2(0>a )在区间]3,2[上有最大值4和最小值1，则b a +的值为▲ ．7.已知72p =，75q =，则lg2用,p q 表示为 ▲ ．8.已知2123()(2,)n n f x x n k k Z -++==∈的图像在[0,)+∞上单调递增，则不等式2()(3)f x x f x ->+的解集为▲ ．9.已知函数f(x)= 22,0,3,0x ax x bx x x ⎧+≥⎪⎨-<⎪⎩为奇函数，则不等式f(x)<4的解集为 ▲ ． 10.已知函数b a x a b x x f ++--+=)2()(22是偶函数，则此函数图象与y 轴交点的纵坐标的最大值是▲ ．11. 设实数1≥a ，使得不等式a ax x ≥+-23，对任意的实数[]2,1∈x 恒成立，则满足条件的实数a 的范围是 ▲ ．12. 定义在R 上的函数f (x )的图象关于点（43-，0）对称，且满足f (x )= -f (x +23)，f (1)=1，f (0)=-2，则f (1)+f (2)+f (3)+…+f (2015)的值为 ▲ ．13.函数22()(1)(1)x axf x x x +=+-是奇函数的充要条件是a = ▲ ． 14. 已知函数()()(1,1)1xf x x x=∈--，下列结论中正确结论的序号为 ▲ ．（1）(1,1)x ∀∈-，等式()()0f x f x -+=恒成立；（2）[)0,m ∀∈+∞，方程()f x m =有两个不等实数根；（3）()12,1,1x x ∀∈-，若12x x ≠，则一定有12()()f x f x ≠；（4）存在无数多个实数k ，使得函数()()g x f x kx =-在(1,1)-上有三个零点数学练习卷——函数（3）答卷班级姓名学号成绩一、填空题（每小题5分，满分70分）1. 2. 3. 4. 5. 6. 7. 8. 9. 10.11.12.13.14.二、解答题（本大题共6小题，共计90分，解答时应写出文字说明、证明或演算步骤）15.(本小题满分14分)已知函数f (x )＝A sin ⎝ ⎛⎭⎪⎫x ＋π4，x ∈R ，且f ⎝ ⎛⎭⎪⎫5π12＝32.(1)求A 的值； (2)若f (θ)＋f (－θ)＝32，θ∈⎝ ⎛⎭⎪⎫0，π2，求f ⎝ ⎛⎭⎪⎫3π4－θ.16． (本小题满分14分)已知函数f (x )＝sin(x ＋θ)＋a cos(x ＋2θ)，其中a ∈R ，θ∈⎝ ⎛⎭⎪⎫－π2，π2. (1)当a ＝2，θ＝π4时，求f (x )在区间[0，π]上的最大值与最小值；(2)若f ⎝ ⎛⎭⎪⎫π2＝0，f (π)＝1，求a ，θ的值．17. (本小题满分14分) 某实验室一天的温度(单位：℃)随时间t (单位：h)的变化近似满足函数关系：f (t )＝10－3cos π12t －sin π12t ，t ∈[0，24)．(1)求实验室这一天的最大温差．(2)若要求实验室温度不高于11℃，则在哪段时间实验室需要降温？18. (本小题满分16分) 已知函数1)(2-=x x f ，|1|)(-=x a x g ．（1）若R x ∈时，不等式)()(x g x f ≥恒成立，求实数a 的取值范围；（2）求函数()()()h x f x g x =+在区间[-2,2]上的最大值．19. (本小题满分16分) 已知函数22()(,,)xx f x aebe cx a b c R -=--∈的导函数()f x '为偶函数，且曲线()y f x =在点(0，f (0))处的切线的斜率为4－c .(1)确定,a b 的值；(2)若c ＝3，判断f (x )的单调性； (3)若f (x )有极值，求c 的取值范围．20. (本小题满分16分) 设函数()(,,)nn f x x bx cn N b c R +=++∈∈（1）设2n ≥，1,1b c ==-，证明：()n f x 在区间1,12⎛⎫⎪⎝⎭内存在唯一的零点；（2）设2n =，若对任意12,x x [1,1]∈-，有2122|()()|4f x f x -≤，求b 的取值范围；（3）在（1）的条件下，设n x 是()n f x 在1,12⎛⎫⎪⎝⎭内的零点，判断数列23,,,nx x x 的增减性.参考答案一、填空题1.(1,1)-．2.．若 21,1,1x x x ≤-≥≥或则3.(2,0)-．4.．3441≤≤m5.3log 2．6. 17. p p q +8.．()()+∞-∞-,31,9.-4∞（，） 10. 2 11. ),25[]23,1[+∞⋃ 12. 2 13.-1 14. 1,3,4二、解答题15.16. [2014·江西卷]解：(1)f (x )＝sin ⎝ ⎛⎭⎪⎫x ＋π4＋2cos ⎝⎛⎭⎪⎫x ＋π2＝ 22(sin x ＋cos x )－2sin x ＝22cos x －22sin x ＝sin ⎝ ⎛⎭⎪⎫π4－x . 因为x ∈[0，π]，所以π4－x ∈⎣⎢⎡⎦⎥⎤－3π4，π4，故f (x )在区间[0，π]上的最大值为22，最小值为－1. (2)由⎩⎪⎨⎪⎧f ⎝ ⎛⎭⎪⎫π2＝0，f （π）＝1，得⎩⎪⎨⎪⎧cos θ（1－2a sin θ）＝0，2a sin 2θ－sin θ－a ＝1. 又θ∈⎝ ⎛⎭⎪⎫－π2，π2，知cos θ≠0，所以⎩⎪⎨⎪⎧1－2a sin θ＝0，（2a sin θ－1）sin θ－a ＝1，解得⎩⎪⎨⎪⎧a ＝－1，θ＝－π6. 17解：(1)因为f (t )＝10－2⎝ ⎛⎭⎪⎫32cos π12t ＋12sin π12t ＝10－2sin ⎝ ⎛⎭⎪⎫π12t ＋π3，又0≤t <24，所以π3≤π12t ＋π3<7π3，－1≤sin ⎝ ⎛⎭⎪⎫π12t ＋π3≤1. 当t ＝2时，sin ⎝ ⎛⎭⎪⎫π12t ＋π3＝1；当t ＝14时，sin ⎝ ⎛⎭⎪⎫π12t ＋π3＝－1. 于是f (t )在[0，24)上取得的最大值是12，最小值是8.故实验室这一天的最高温度为12 ℃，最低温度为8 ℃，最大温差为4 ℃.(2)依题意，当f (t )>11时，实验室需要降温．由(1)得f (t )＝10－2sin ⎝ ⎛⎭⎪⎫π12t ＋π3，故有10－2sin ⎝ ⎛⎭⎪⎫π12t ＋π3>11，即sin ⎝ ⎛⎭⎪⎫π12t ＋π3<－12. 又0≤t <24，因此7π6<π12t ＋π3<11π6，即10<t <18.故在10时至18时实验室需要降温．18. （1）不等式()()f x g x ≥对x ∈R 恒成立，即2(1)|1|x a x --≥（*）对x ∈R 恒成立，①当1x =时，（*）显然成立，此时a ∈R ；②当1x ≠时，（*）可变形为21|1|x a x -≤-，令21,(1),1()(1),(1).|1|x x x x x x x ϕ+>⎧-==⎨-+<-⎩ 因为当1x >时，()2x ϕ>，当1x <时，()2x ϕ>-，所以()2x ϕ>-，故此时2a -≤.综合①②，得所求实数a 的取值范围是2a -≤. …………………6分（2）当3a <-时，()h x 在[2,2]-上的最大值为0；当30a -<≤时，()h x 在[2,2]-上的最大值为3a +；当0a ≥时，()h x 在[2,2]-上的最大值为33a +。

高三化学周练一参考答案

蓝天家教网伴您快乐成长高三化学周练一参考答案一、选择题（2）略（3）氯气腐蚀橡皮管（4）将U型管放在冰水浴中。

2HCl+Ca(OH)2=CaCl2+2H2O 发生装置和U型管之间放饱和氯化钠溶液16．（1）4mol/L，溶液的密度（2）2NaClO3+SO2+H2SO4=2ClO2+2NaHSO4 B(3)A(4)连续测定溶液的PH值（5）BED（6）重结晶17．（1）四VIIA（2）可防止氯气、溴与水反应（3）SO2+Br2+2H2O=4H++SO42-+2Br-（4）温度高，水也被蒸出；温度低，溴不能完全蒸出（5）分液漏斗下口（6）直接蒸馏，海水中溴的浓度低，成本高18．（1）淀粉（2）Fe3I8+4K2CO3=8KI+4CO2+Fe3O4(3)过氧化氢是绿色氧化剂，不产生污染，且不会使生成的I2进一步被氧化。

（4）萃取（5）蒸馏烧瓶、温度计、冷凝管（6）IO3-+5I-+6H+=3I2+3H2O19．（1）3Br2+6NaOH=5NaBr+NaBrO3+3H2O(2)NH4++Al3++5OH-=NH3+AlO2-+3H2ONH4++Al3++2SO42-+2Ba2++5OH-=NH3+AlO2-+2BaSO4+3H2O(3)NH2Cl+H2O=HClO+NH3(4)26HClO3=10HClO4+15O2+8Cl2+8H2O(5)2KClO3+4HCl=2KCl+2ClO2+Cl2+2H2O高温20.2C+SnO2====Sn+2CO Sn2++2e=Sn△(1)MnO2+4HCl(浓)===MnCl2+Cl2+2H2O(2)B 反应放热，使锡熔化（3）少温度计连一个装有碱石灰的干燥管（4）在A和B 之间依次连接装有饱和食盐水和浓硫酸的洗气瓶21．（1）ClFO4(2)F2+HClO4=ClFO4+HF(3)吸收氟化氢（4）液氧提供的低温使X成为固体，便于X的分离（5）增大氟气和高氯酸的接触面积（6）石墨与高氯酸反应22．（1）次氯酸钙或氯酸钾（2）2.5mol/L(3)5mol/L 偏高。

上海市上海中学高三上学期英语周练试题1 含答案

上海中学高三英语周练II. Grammar and VocabularySection ADirections: A fter reading the passages below, fill in the blanks to make the passages coherent and grammatically correct. For the blanks with a given word, fill in each blank with the proper form of the given word; for the other blanks, use one word that best fits each blank.(A)We know the famous ones-the Thomas Edisons and the Alexand er Graham Bells-but what about the__26__________( famous) inventors? What about the people who invented the traffic light and the windshield wiper ? Shouldn't we know who they are?Joan McLean thinks so. In fact, McLean, a professor of physics at Mountain University in Range, feels so strongly about this matter _27_________ she's devel oped a course on the topic. In addition to l earning "who"invented "what", however, McLean also likes her stud ents to learn the answers to the "why" and "how" questions. According to McLean, When stud ents learn the answers to these questions, they are better prepared to recognize opportunities for inventing and more motivated to give _28______________ a try.So, just what is the story behind the windshield wiper? Well, Mary Anderson came up with the id ea in 1902 after a visit to New York City. The day was col d and stormy, but And erson still wanted to see the sights,so she jumped aboard a streetcar. Noticing that the driver was struggling to see _29___________ the snow covering the windshield, she found herself _30__________ why there couldn't be a builtin device for cleaning the wind ow. Still wondering about this when she returned home to Birmingham, Alabama, Anderson started drafting out solutions. One of her ideas, a lever (操作杆) on the inside of a vehicl e that would control 31__________ arm on the outside,became the first windshield wiper.Today we benefit from countless inventions and innovations. It's hard to imagine driving without Garrett A. Morgan's traffic light. It's equally impossible to picture a worl d without Katherine J. Bl odgett's innovation that makes glass invisible. _32_____________ you picture life without clear wind ows and eyeglasses?(B)There are a few things in life more irritating: you are mid conversation with a friend, and sudd enly she bursts out laughing,33_________(make) you think you’ve mad e a brilliant j oke. But then she says, “Sorry, I wasn’t laughing at you. I just saw something really fun on a micro blog.” Now the whol e worl d is beginning to lose patience with this phenomenon known as phubbing: snubbing others in a social setting __34___________checking your phone.In fact, phubbing is just one symptom of our increasing depend ence on mobile phones and the Internet which is replacing normal social interaction. According to a recent pollcarried out by a Sunday newspaper in Britain, a third of Britons__35_______(survey) admitted to being phubbers and more than a quarter said they would answer their phones in the middle of a face to face conversation.36_____________pointing or picking your nose, phubbing is also widely considered rud e behavior in public places. Lately , a Stop Phubbing campaign group has started in Australia and at least five __37___________have sprung up in its wake __38___________anger and discontent at the lack of manners grow.The campaign’s creator , Alex Haigh,23, from Melbourne, said :“A group of friends and I __39__________(chat) the other day when someone raised ho annoying being ignored by peopl e on mobil es was.” He has created a website __40_________companies can d ownload posters to discourage phubbing and even placards for weddings.Section BDirections: Complete the following passage by using the words in the box. Each word can only be used once. Note that there is one word more than you need.Recently the Department of Planning of New York _41________ a report which laid bare a full scal e of the city. In 1970, 18 percent of the city's population was foreign-born. By 1995, the figure had 42______ to 33 percent, and another 20 percent were the US-born offspring of immigrants. So immigrants and their children now form. a (n)_43_____ of the city's population.Who are these New Yorkers? Why d o they come here? Where are they from? OK, time to drop the "they". I'm one of the them. The last question at least is easy to answer: we come from everywhere. In the list of the top 20 44________ nations of those sending immigrants to New York between 1990 and 1994 are six countries in Asia, five in the Caribbean, four' in Latin America, three in Europe, plus Israel and former Soviet Union. And when we immigrants got here we 45_______up our sleeves. “If you are not ready to work when you get to New York,” says a friend of mine , “you’d better hit the road.”The mayor of New York once said, "Immigration has__46_________ the unique character and drive the economic engine of New York City." He believes that immigrants are at the heart of what makes Now York great. In Europe, by contrast, it is much more common to hear politicians worry about the loss of "_47________" that immigration brings to their societies. In the quarter century' since 1970, the United States__48_______ about 12.5 million legal immigrants, and has absorbed them into its social structures with an ease beyond the imagination of other nations. Since these immigrants are__49___________l and hard-working, they will help America to make a(n) _50_______ start in the next century.III. Reading ComprehensionSection ADirections: For each blank in the foll owing passage there are four words or phrases marked A, B, C and D. Fill in each blank with the word or phrase that best fits the context.Everyone in business has been told that success is all about attracting and retaining (留住) customers. It sounds simple and achievable. But, __51__, words of wisdom are soon forgotten. Once companies have attracted customers they often __52__ the second half of the story. In the excitement of beating off the competition, negotiating prices, securing orders, and delivering the product, managers tend to become carried away. They forget what they regard as the boring side of business -- __53__ that the customer remains a customer.__54__ to concentrate on retaining as well as attracting customers costs business huge amounts of money annually. It has been estimated that the average company loses between 10 and 30 per cent of its customers every year. In constantly changing __55__, this is not surprising. What is surprising is the fact that few companies have any idea how many customers they have lost.Only now are organizations beginning to wake up to those lost opportunities and calculate the __56__ implications. Cutting down the number of customers a company loses can make a big __57__ in its performance. Research in the US found that a five per cent decrease in the number of defecting (流失的) customers led to __58__ increases of between 25 and 85 per cent.In the US, Domino’s Pizza estimates that a regular customer is worth more than $5,000 over ten years. A customer who receives a poor quality product or service on their first visit and __59__ never returns, is losing the company thousands of dollars in __60__ profits (more if you consider how many people they are likely to tell about their bad experience).The logic behind cultivating customer __61__ is impossible to deny. “In practice most companies’ marketing effort is focused on getting customers, with little attention paid to __62__ them”, says Adrian Payne of Cornfield University’ School of Management. “Research suggests that there is a close relationship between retaining customers and making profits. __63__ customers tend to buy more, are predictable and usually cost less to service than new customers. Furthermore, they tend to be less price __64__, and may provide free word-of-mouth advertising. Retaining customers also makes it __65__ for competitors to enter a market or increase their share of a market.51..A. in particular B. in reality C. at least D. first of all52. A. emphasize B. doubt C. overlook D. believe53. A. Denying B. ensuring C. arguing D. proving54. A. Moving B. Hoping C. Starting D. Failing55..A. markets B. tastes C. prices D. expenses56. A. culture B. social C. financial D. economical57. A. promise B. plan C. mistake D. difference58 .A. cost B. opportunity C. profit D. budget59. A.as a result B. on the whole C. in conclusion D. on the contrary60. A. huge B. potential C. extra D. reasonable61. A. beliefs B. loyalty C. habits D. interest62. A. altering B. understanding C. keeping D. Attracting63. A. Assumed B. Respected C. Established D. Unexpected64. A. agreeable B. flexible C. friendly D. sensitive65. A. unfair B. difficult C. essential D. convenientSection BDirections: Read the following three passages. Each passage is followed by several questions or unfinished statements. For each of them there are four choices marked A,B,C,D. Choose the one that fits best according to the information given in the passage you have just read.(A)If you are a male and you are reading this, congratulations: you are a survivor. According to statistics, you are more than twice as likely to die of skin cancer than a woman, and nine times more likely to die of AIDS. Assuming you make it to the end of your natural term, about 78 years for men in Australia, you will die on average five years before a woman.There are many reasons for this, men take more risks than women and are more likely to drink and smoke, but perhaps more importantly, men d on't go to the doctor."Men aren't seeing d octors as often as they should," says Dr. Gullotta, "This is particularly so for the over-40s, when diseases tend to strike."Gullotta says a healthy man shoul d visit the d octor every year or two. For those over 45,it should be at least once a year.Two months ago Gullotta saw a 50-year-old man who had delayed d oing anything about his smoker’s cough for a year.When I finally saw him it had already spread and he has since died from ling cancer,”he says , “Earlier detection and treatment may not have cured him, bu t it woul d have prolonged his life.”According to a recent survey, 95%of women aged between 15 and early 40s see a doctor once a year, compared to 70% of men in the same age group."A lot of men think they are invincible (不可战胜的)" Gullotta says "They only come in when a friend drops d ead on the golf course and they think 'Geez, if it coul d happen tohim, …'"Then there is the ostrich (鸵鸟) approach, "Some men are scared of what might be there and would rather not know," says Dr. Ross Cartmill."Most men get their cars serviced more often than they service their bodies," Cartmill says. He believes most diseases that commonly affect men coul d be addressed by preventive check-ups.Regular check-ups for men woul d inevitably (不可避免地) place stress on the public purse. Cartmill says. "But prevention is cheaper in the l ong run than having to treat the diseases. Besid es, the ultimate cost is far greater. It’s called premature d eath"66.Why d oes the author congratulate his mal e readers at the beginning of the passage?A. They are more likely to suffer diseases today.B. Their average life span has been considerably extended.C. They have lived long enough to red this article.D. They are sure to enjoy a l onger and happier life.67.Which of the foll owing best completes the sentence "Geez, if it could happen to him,…" in paragraph8?A. it coul d happen to me, too.B. I shoul d avoid playing golfC. I should consider myself lucky.D. it would be a big misfortune.68What does Dr. Ross Cartmill mean by "the ostrich approach" in paragraph 9?A .casual attitude towards one's health conditions.B. A new treatment for certain psychol ogical probl ems.C. Refusal to get medical treatment for fear of the pain involved.D. Unwillingness to find out about one's disease because of fear.69.What does Cartmill say about regular check-ups for men?A. They may increase public expenses.B. They will save money in the long run.C. They may cause psychol ogical stress on men.D. They will enable men to live as long as women.(B)Doctors have been advising us for years to "use it or lose it": that is, to stay as intellectually active as possibl e into our waning years in order to avoid dementia. But the latest research shows that brain training comes at a price.In a study of 1,157 men and women age 65 or ol der, researchers led by Dr. Robert Wilson at Rush University Medical Center in Chicago found that people who remained intellectually stimulated —by playing cards or other games, reading or visiting museums —were diagnosed with dementia later than those who were not as cognitively active. But once dementia set in, the group who participated in mentally stimulating activities experienced a much more rapid cognitive decline. Over the 12-year study, for each additional point they gained on a measure of cognitive activity, the intellectually stimulated group experienced a 52% greater decline in cognitive impairment, after being diagnosed with dementia.“Brain activity is not stopping the und erlying neu robiol ogy of d ementia, but for a while, it seems to be effective in delaying the ad ditional appearance of symptoms," says Wilson. "But the benefit of delaying the initial symptoms comes at the cost of more rapid progression of dementia once it makes its appearance."While brain exercises can help the brain continue to function d espite the accumulating biological changes und erlying dementia and Alzheimer's, at some point, says Wilson, the scales tip — that activity can no longer compensate for the growing volume of deteriorating alterations in the brain. "At that point, the patient is pretty much at the mercy of the pathol ogy," he says. And that's why, once the symptoms of dementia become obvious, those who were able to push off their diagnosis are likely to be at a more advanced stage of disease.The findings, published Wednesday in Neurol ogy, should not discourage people from remaining cognitively active, says Dr. William Thies, chief medical officer of the Alzheimer's Association, and in fact raises interesting questions about how we as a society shoul d approach age-related brain changes. Surveys consistently show that most of us woul d prefer to remain as functionally intact as possibl e and experience a short period of physical or mental disability before d eath. Gradual cognitive decline, which is the hallmark of Alzheimer's disease, is challenging for patients, their caregivers and society, as the health costs of chronic care continue to climb. But the current study suggests that more people may be able to telescope their mental d ecline into a shorter and more concentrated time period. "I think the results suggested by this paper are something that peopl e would regard as positive," he says. "And this is the sort of study we really need if we are ever going to understand how to manage all aspects of d ementia as a society."70. The word “dementia” can be best replaced by _______________________________.A. mental diseaseB. brain damageC. cognitive declineD. Biological changes71. The sentence underlined suggests that when the brain exercises can no longer compensate for the worsening alterations in the brain, __________.A. the volume of the worsening alterations in brain determines the seriousness of the diseaseB. the patient no l onger needs to d o brain exercises and has to be taken care of by the d octorsC. the d octors can only treat the patient based on his pathol ogical conditionsD. the accumulating biol ogical changes underlying dementia can’t be ignored by the patient72. According to Dr. William Thies, the findings shoul d be viewed as__________.A. discouragingB. interestingC. challengingD. positive73. What can we infer from the passage?A. Brain training is very expensive for those who want to stay cognitively active.B. The costs of taking care of an Alzheimer’s patient continue to go up.C. Those who d o brain exercises will definitely suffer from d ementia at last.D. We need more studies to understand how to manage dementia as a society.(C)The modern Olympic Games, founded in 1896,began as contests between individuals, rather than among nations , with the hope of promoting world peace through sportsmanship . In the beginning ,the games were open only to amateurs. An amateur is a person whose involvement in an activity--from sports to science or the arts--is purely for pleasure . Amateurs , whatever their contributions to a field, expect to receive no form of compensation; professional ,in contrast ,perform their work in ord er to earn a living.From the perspective of many athletes, however , the Olympic playing filed has been far from level. Restricting the Olympic to amateurs has preclud ed (排除）the participation of many who could not afford to be unpaid. Countries have always d esired to send their best athletes , not their wealthiest ones, to the Olympic Games.A sl ender and imprecise line separates what we call “financial support” from “earning money.” Do athletes “earn money” if they are reimbursed（补偿）for travel expenses? What if they are paid for time l ost at work or if they accept free clothing from a manufacturer or if they teach sports for a living? The runner Eric Lid dell was the son of poor missionaries; in 1924 the British Olympic Committee financed his trip to the Olympics, where he won a gol d and a bronze medal. Coll ege scholarships and support from the United States Olympic Committee mad e it possibl e for American track stars Jesse Owens and Wilma Rudolph and speed skater Dan Jansen to train and compete. When the Soviet Union and its allies joined the games in 1952, the definition of amateur became still muddier. Their athletes did not have to balance jobs and training because as citizens in communist regimes, their government financial support was not considered payment for jobs.In 1971 the International Olympic Committee(IOC) removed the word amateur from the rules, making it easier for athletes to find the support necessary to train and compete. In 1986 the IOC all owed professional athletes into the games.There are those who regret the disappearance of amateurism from the Olympic Games. For them the games l ost something special when they became just another way for athletes to earn money. Others say that the designation of amateurism was always questionable; theyargue that all competitors receive so much financial support as to make them paid professionals. Most agree, however, that the debate over what constitutes an“amateur”will continue for a l ong time.74. One might infer that _______________________.A. devel oping Olympic-level skills in athletes is costlyB. professional athletes are mostly interested in financial rewardsC. amateurs does not expect to earn money at the sport that is playedD. amateurs athletes have a better attitud e than professionals d o75. The state ment“the playing field has been far from level”means that__________.A. the ground the athletes played on was in bad conditionB. the poorer players were given some advantagesC. the rules did not work the same way for everyoneD. amateurs were inferior to the professionals in many ways76. The financial support given to athletes by the Soviet government can best be compared to ________________.A. a gift received on a special occasion, such as a birthdayB. money received from a winning lottery ticketC. an all owance paid to a childD. Money from charity organization77. One can conclude that the Olympic Organizing Committee _________________.A. has hel d firm to its original vision of the Olympic gamesB. has struggled with the definition of amateur over the yearsC. regards itself as an organization for professional athl etes onlyD. did nothing but stop all owing communists to participateSection DDirections: Read the passage carefully and answer the questions or complete the statements in no more than 12 words."Severe fatigue(疲乏), very weak. I could hardly walk d own the bl ock," says Wendy Moro. Why, she wondered, then, Wendy and her d octor begin to suspect her plate. "A few times a week I was having fish, whether it was once or four times," says Wendy. "What kind of fish? Swordfish, tuna and sea bass, the highest mercury- content fish sold in the commercial market," says Dr. Jane Hightower.Mercury(汞) enters the ocean with commercial pollution. It works its way up the food chain, and apparently into some of the most popular fish on the market. Wendy's doctor, Dr. Jane Hightower, was so suspicious that she began testing her Bay Area patients. All consumed large amounts offish, and an overwhelming majority tested high for mercury in their systems."I was seeing hair loss, fatigue, muscle ache, headache, feeling just an ill feeling."Hightower said.The symptoms began to clear up when Hightower cut the amount of fish in their diets. "It was so obvious, but the problem was still unknown to the public," she said. "I even wanted to rent a tent and a tambourine."(A tambourine is a small one-sided drum with metal disks around its rim.) Her published findings drew national attention. But despite her study, there is still fierce debate over how much fish is safe to eat, and how much mercury consumers are actually eating. So we decid ed to do our own test.According to the EPA (Environmental Protection Agency), the safe l evel of mercury intake for a 120-pound woman like Wendy is a little over 38 micrograms per week. On average, a single serving of tuna purchased here in the Bay Area contained more mercury than the EPA recommends a woman of Wendy's size eat for an entire week. Sea bass had nearly twice that level, and swordfish nearly six times the EPA's safe mercury intake for a week, in a single serving.Whil e there is little scientific data on how the body reacts to high levels of mercury, it has been linked to symptoms ranging from muscle pain to hair loss, birth defects, and muscle fatigue And, as in our testing, the evidence is mounting that the larger the fish, the more the exposure.(Note: Answer the questions or complete the statement in NO MORE THAN TEN WORDS.)81. The popular fish on the market obtain mercury through and .82. When Dr. Hightower "wanted to rent a tent and a tambourine", she meant to .83. What did Dr. Hightower do with the information she discovered?_________________________________________________________________________84. What should people do according to the test done by the EPA?__________________________________________________________________________第II卷I. TranslationDirections :Translate the following sentences into English, using the words given in the brackets.1.务必放弃这种不切实际的想法，否则你将一事无成。

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高三第一次周练
考试范围：全部考试时间：2020.8.7 命题人：侯竹春满分：100分
一、选择题(每小题7分，
共56分）
1.设，则
A. B. C. D.
2.某地区经过一年的新农村建设，农村的经济收入增加了一倍．实现翻番．为更好地了解该地区农村的经济收入变化情况，统计了该地区新农村建设前后农村的经济收入构成比例．得到如下饼图：
则下面结论中不正确的是
A.新农村建设后，种植收入减少
B.新农村建设后，其他收入增加了一倍以上
C.新农村建设后，养殖收入增加了一倍
D.新农村建设后，养殖收入与第三产业收入的总和超过了经济收入的一半
3.设为等差数列的前项和，若，，则
A. B. C. D.
4. 函数的图像大致为 ( )
A. B. C. D.
5.设函数，若为奇函数，则曲线在点处的切线方程为
A. B. C. D.
6.某圆柱的高为2，底面周长为16，其三视图如图所示，圆柱表面上的点在正视图上的对应点为，圆柱表面上的点在左视图上的对应点为，则在此圆柱侧面上，从到的路径中，最短路径的长度为（）
A. B. C. D.2
7.设抛物线C：y2=4x的焦点为F，过点（–2，0）且斜率为的直线与C交于M，N两点，则=
A.5
B.6
C.7
D.8
8.已知函数．若g（x）存在2个零点，则a的取值
范围是
A.[–1，0）
B.[0，+∞）
C.[–1，+∞）
D.[1，+∞）
二、填空题(每小题7分，
共14分）
9.的展开式中的系数为_________.
10.从2位女生，4位男生中选3人参加科技比赛，且至少有1位女生入选，则不同的选法共有_____________种．（用数字填写答案）
三、解答题(每小题15分，
共30分）
11.在平面四边形中，，，，.
（1）求；
（2）若，求.
12.如图，四边形为正方形，分别为的中点，以为折痕把折起，使点到达点的位置，且.
（1）证明：平面平面；
（2）求与平面所成角的正弦值.
参考答案
一、选择题
1.答案：C
解析：首先根据复数的运算法则，将其化简得到，根据复数模的公式，得到，从而选出正确结果.
解：因为，
所以，故选C.
2.答案：A
解析：首先设出新农村建设前的经济收入为M，根据题意，得到新农村建设后的经济收入为
2M，之后从图中各项收入所占的比例，得到其对应的收入是多少，从而可以比较其大小，并且得到其相应的关系，从而得出正确的选项.
解：设新农村建设前的收入为M，而新农村建设后的收入为2M，
则新农村建设前种植收入为0.6M，而新农村建设后的种植收入为0.74M，所以种植收入增加了，所以A项不正确；
新农村建设前其他收入我0.04M，新农村建设后其他收入为0.1M，故增加了一倍以上，所以B 项正确；
新农村建设前，养殖收入为0.3M，新农村建设后为0.6M，所以增加了一倍，所以C项正确；新农村建设后，养殖收入与第三产业收入的综合占经济收入的，所以超过了经济收入的一半，所以D正确；
故选A.
3.答案：B
解析：首先设出等差数列的公差为，利用等差数列的求和公式，得到公差所满足的等量关系式，从而求得结果，之后应用等差数列的通项公式求得，从而求得正确结果.
解：设该等差数列的公差为，
根据题中的条件可得，
整理解得，所以，故选B.
4.答案：B
解析：通过研究函数奇偶性以及单调性，确定函数图像.
解：为奇函数，舍去A,
舍去D;
，
所以舍去C；因此选B.
5.答案：D解析：利用奇函数偶此项系数为零求得，进而得到的解析式，再对求导得出切线的斜率，进而求得切线方程.
解：因为函数是奇函数，所以，解得，
所以，，
所以，
所以曲线在点处的切线方程为，
化简可得，故选D.
6.答案：B解析：首先根据题中所给的三视图，得到点M和点N在圆柱上所处的位置，点M在上底面上，点N在下底面上，并且将圆柱的侧面展开图平铺，点M、N在其四分之一的矩形的对角线的端点处，根据平面上两点间直线段最短，利用勾股定理，求得结果.
解：根据圆柱的三视图以及其本身的特征，
可以确定点M和点N分别在以圆柱的高为长方形的宽，圆柱底面圆周长的四分之一为长的长方形的对角线的端点处，
所以所求的最短路径的长度为，故选B.
7.答案：D解析：首先根据题中的条件，利用点斜式写出直线的方程，涉及到直线与抛物线相交，联立方程组，消元化简，求得两点，再利用所给的抛物线的方程，写出其焦点坐标，之后应用向量坐标公式，求得，最后应用向量数量积坐标公式求得结果.
解：根据题意，过点（–2，0）且斜率为的直线方程为，
与抛物线方程联立，消元整理得：，
解得，又，
所以，
从而可以求得，故选D.
8.答案：C解析：首先根据g（x）存在2个零点，得到方程有两个解，将其转化为有两个解，即直线与曲线有两个交点，根据题中所给的函数解析式，画出函数的图像（将去掉），再画出直线，并将其上下移动，从图中可以发现，当时，满足与曲线有两个交点，从而求得结果.
解：画出函数的图像，在y轴右侧的去掉，
再画出直线，之后上下移动，
可以发现当直线过点A时，直线与函数图像有两个交点，
并且向下可以无限移动，都可以保证直线与函数的图像有两个交点，
即方程有两个解，
也就是函数有两个零点，
此时满足，即，故选C.
9. 解析：写出，然后可得结果
解：由题可得
令,则
所以
10.答案：16
解析：首先想到所选的人中没有女生，有多少种选法，再者需要确定从6人中任选3人总共有多少种选法，之后应用减法运算，求得结果.
解：根据题意，没有女生入选有种选法，
从6名学生中任意选3人有种选法，
故至少有1位女生入选，则不同的选法共有种，故答案是16.
11.解析：分析：(1)根据正弦定理可以得到，根据题设条件，求得，结合角的范围，利用同角三角函数关系式，求得；
(2)根据题设条件以及第一问的结论可以求得，之后在中，用余弦定理得到所满足的关系，从而求得结果.
解：（1）在中，由正弦定理得.
由题设知，，所以.
由题设知，，所以.
（2）由题设及（1）知，.
在中，由余弦定理得
.所以.
12.答案：(1).由已知可得，BF⊥PF，BF⊥EF，又，所以BF⊥平面PEF.
又平面ABFD，所以平面PEF⊥平面ABFD.(2)..
解析：分析：(1)首先从题的条件中确定相应的垂直关系，即BF⊥PF，BF⊥EF，又因为，利用线面垂直的判定定理可以得出BF⊥平面PEF，又平面ABFD，利用面面垂直的判定定理证得平面PEF⊥平面ABFD.
(2)结合题意，建立相应的空间直角坐标系，正确写出相应的点的坐标，求得平面ABFD的法向量，设DP与平面ABFD所成角为，利用线面角的定义，可以求得，得到结果.
解：（1）由已知可得，BF⊥PF，BF⊥EF，又，所以BF⊥平面PEF.
又平面ABFD，所以平面PEF⊥平面ABFD.
（2）作PH⊥EF，垂足为H.由（1）得，PH⊥平面ABFD.
以H为坐标原点，的方向为y轴正方向，为单位长，建立如图所示的空间直角坐标系H?xyz.
由（1）可得，DE⊥PE.又DP=2，DE=1，所以PE=.又PF=1，EF=2，故PE⊥PF.
可得.
则为平面ABFD的法向量.
设DP与平面ABFD所成角为，则.
所以DP与平面ABFD所成角的正弦值为.。