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若函数在R上可导,且 , 则(     )

A . B . C . D . 不能确定
Fall is gold, winter is_______.
A . white B . black C . blue
实验小组的同学利用如图所示的实验装置探究“光的反射定律”.

  1. (1) 让一细光束紧贴硬纸板E射到平面镜上的O点,在硬纸板E上可看到入射光线AO,若将纸板F向前或向后折,在纸板F上不能看到反射光线,这说明
  2. (2) 同学们在探究反射角和入射角的关系时,改变了角大小,先后做三次实验,并将测得的数据记录在表中.

    实验次数

    入射角

    反射角

    1

    20°

    20°

    2

    45°

    45°

    3

    60°

    60°

    分析表中数据得出结论是:.进行多次实验的目的是(填A. “防止实验的偶然性”       B.“减小实验误差”)

  3. (3) 同学们还发现,若将一束光贴着纸板F沿BO射到O点,则光沿图中的OA方向射出,这是因为在反射现象中光路是
  4. (4) 本实验中硬纸板的作用是
完形填空

The story was a true one and still moved me deeply. Thirty years ago,I got to know a    1lady named Rose. She had no kids and lived alone.    2I went to visit her,I always took Rose some coffee and food. One day she said she     3 to invite me to have hunch.

We walked from my work place to a little restaurant on David Street   4the way, I began to worry:I knew that she had no money,but if I offered to    5the lunch. I was afraid I would hurt her.

There were many people in the   6and all of them were happy. Rose told me to sit and drink coffee by the window. Then she went to    7in the kitchen. After about 20minutes,she came out and sat with me. She just paid for one meal and we started to    8the delicious food together. She told   9 that the restaurant let people work for a meal if they had no money,or would give them a free meal if they were not able to work. To my surprise,she also explained that the works who were working there were all volunteers. ",10.

I   11remember the beautiful afternoon I shared with Rose. We had a meal together only once,12it was paid by Rose's work. The weather was13and bright,and everyone's smile was warm and bright as well.

I'm still thinking that life cannot be easy to us,but we can still do14for our friends and neighbors. The world will be    15if everybody would like to share happiness with others. It will never be dark if there is a light in everyone's heart.

(1)
A . rich B . poor C . strange D . crazy
(2)
A . When B . After C . Until D . Unless
(3)
A . wanted B . forgot C . missed D . promised
(4)
A . By B . In C . On D . Out of
(5)
A . pay for B . ask for C . look for D . care for
(6)
A . park B . restaurant C . hotel D . bar
(7)
A . sit B . rest C . stay D . work
(8)
A . buy B . cook C . enjoy D . drink
(9)
A . her B . him C . me D . you
(10)
A . in fact B . at first C . at once D . on time
(11)
A . never B . still C . hardly D . already
(12)
A . So B . But C . Though D . Because
(13)
A . hot B . cold C . cool D . warm
(14)
A . something B . anything C . nothing D . everything
(15)
A . colder B . nicer C . harder D . worse
抄写:按英文格式把下面的句子抄写在格子上。

Who's this man in the picture? Oh, he's a film star. Look, he has a big, long nose.

 下图为南极地区和北极地区图。读图,完成下面小题。

  1. (1)  下列关于南极地区和北极地区的说法,错误的是(   )
    A . 南极地区以南极大陆为主,北极地区以北冰洋为主 B . 北极地区和南极地区都有丰富的矿产资源 C . 与北极地区比,南极地区更加寒冷,冰雪覆盖更多 D . 南极地区和北极地区迄今为止,都没有定居人口
  2. (2)  近些年来,伴随着世界各国的极地科考热,使极地地区环境受到了不同程度的破坏。下列行为有利于保护两极地区自然环境的是(   )
    A . 进行国际合作,共同保护生态环境 B . 大量捕杀鲸鱼等进行科学研究 C . 将科考垃圾埋藏于冰层之下 D . 在极地地区进行核武器实验
在△ABC中,G为重心,BE为AC的中线, = (λ∈R),则λ的值为
质量为m的高空遥感探测卫星在距地球表面高为h处绕地球做匀速圆周运动.若地球质量为M,半径为R,引力常量为G.求:

  1. (1) 探测卫星的线速度;

  2. (2) 探测卫星绕地球运动的周期;

  3. (3) 探测卫星的向心加速度.

 随着互联网的发展,青少年上网现象越来越普遍。但是,网上不良信息的出现,网上交往规则的丧失,时刻威胁着涉世不深的青少年,严重影响了青少年的健康成长。结合材料运用所学的知识,回答:

  1. (1) 请举出几种“网上不良信息”。

  2. (2) 青少年进行网络交往应遵循哪些规则?

  3. (3) 请为青少年提几条自我保护的具体措施。

下列关于人体细胞增殖、分化、衰老、凋亡和癌变的叙述,正确的是(  )
A . 细胞的分化程度越高,全能性越强 B . 癌细胞具有细胞增殖失控的特点 C . 正常细胞的衰老凋亡必将使个体衰老死亡 D . 幼年个体生长需细胞增殖,成年后不需细胞增殖
已知为不重合的两个平面,直线那么“”是“”的(   )

A . 充分而不必要条件 B . 必要而不充分条件 C . 充分必要条件 D . 既不充分也不必要条件
给划线字选择正确读音

管(jǐn  jìn)    小子(zhǎo  zhuǎ)   着(fá  fàn)

然(zòu  zhòu)   特(shū  zhū)       呼(yù  yú)

一根2米长的铁丝,先用去它的 ,再用去它的 ,还剩下这根铁丝的(   )。
A . B . C . D .
下列函数中,自变量x的取值范围是x≥2的是(   )

A . B . C . D .
在生活中,调节我们行为的规则有很多种。如图《让座》体现的是(  )

A . 纪律 B . 规章 C . 法律 D . 道德
如图,平行于x轴的直线l与Y轴、直线y=3x、直线y=x分别交于点A、B、C.则下列结论正确的个数有(   )

①∠AOB+∠BOC=45;② =2AB;

=10 ;  ④ =

A . 1个 B . 2个 C . 3个 D . 4个
如图,边长为1的正方形ABCD绕点A逆时针旋转45°后得到正方形AB1C1D1 , 边B1C1与CD交于点O,则图中阴影部分的面积为

已知集合 ,且 ,则实数 ;集合 的子集的个数为 .
下列四组生物中,能生活在同一生态系统中的是

A . 猎豹和猕猴 B . 莲花和海带 C . 丹顶鹤和仙人掌 D . 玉米和大豆

如图1,△ABC和△DEF中,AB=AC,DE=DF,∠A=∠D.


  1. (1) 求证:

  2. (2) 由(1)中的结论可知,等腰三角形ABC中,当顶角∠A的大小确定时,它的对边(即底边BC)与邻边(即腰AB或AC)的比值也就确定,我们把这个比值记作T(A),即T(A)= 的对边(底边)/的领边(腰)= ,如T(60°)=1.

    ①理解巩固:T(90°)=,T(120°)=,若α是等腰三角形的顶角,则T(α)的取值范围是

    ②学以致用:如图2,圆锥的母线长为9,底面直径PQ=8,一只蚂蚁从点P沿着圆锥的侧面爬行到点Q,求蚂蚁爬行的最短路径长(精确到0.1).

    (参考数据:T(160°)≈1.97,T(80°)≈1.29,T(40°)≈0.68)

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