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题目列表(包括答案和解析)

.— Do you like a house with no garden?

    —________ , But anyhow, it's better to have one than none.

  A. Not really           B. Not especially

C. Not a bit           D. Not a little

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.______was known to them all that William had broken his promise______ he would give each of them a gift.

A. As, which        B. What, that      C. It , that      D. It , which

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.—Do you feel like ________ there or shall we take a bus?

    —I’d like to walk. But since there isn't much time left, I'd rather we________ a taxi.

  A. walking; hire           B. to walk; hire            C. to walk; hired   D. walking; hired

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.—Without your help, we _____ this task on time.

—My pleasure.

A. don’t finish        B. will not finish       C. didn’t finish      D. would not have finished

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C
"Reduce, reuse and recycle, this familiar environmentalist slogan tells us how to reduce the amount of rubbish that ends up in landfills and waterways.
The concept is being used to deal with one possibly dangerous form of waste –--- electronic junk (电子垃圾), such as old computers, cell-phones, and televisions. But this process for managing e-waste may be used in an unscrupulous(不择手段的) way more often than not used, a recent report suggests.
“A lot of these materials are being sent to developing nations under the excuse of reuse –--- to bridge the digital divide,” said Richard Gutierrez, a policy researcher.
One of the problems is that no one proves whether these old machines work before they hit the seaways. Because of this, the report says, e-waste is a growing problem in Lagos, Nigeria, and elsewhere in the developing world. Much of the waste ends up being thrown away along rivers and roads. Often it’s picked apart by poor people, who may face dangerous exposure to poisonous chemicals in the equipment.
Businessmen also pay workers a little money to get back materials such as gold and copper. This low-tech recovery process could expose workers and the local environment to many dangerous materials used to build electronics. According to Gutierrez, this shadow economy exists because the excuse of recycling and reusing electronics gives businessmen “a green passport” to ship waste around the globe. “Developing nations must take upon some of the responsibility themselves,” Gutierrez said. But, he added, “A greater portion of this responsibility should fall on the exporting state.”
China, for example, has become a dumping(倾倒,堆放) place for large amounts of e-waste. The nation is beginning to take action to stop the flow of dangerous materials across its borders. The Chinese government, after many years of denial(否认), is finally beginning to take the lead.
70.What does the fourth paragraph mainly discuss?
A. Old computers and TVs still work before they are sent abroad.
B. Poor people break up e-waste to collect some valuable materials.
C. A lot of e-waste is dumped in developing countries.
D. The problem of e-waste is growing in developing countries.
71.From what Gutierrez said we can learn that ________.
A. exporting countries should mainly be responsible for this problem.
B. neither rich nor poor countries should be blamed for this problem
C. developing countries should be responsible for this problem
D. poor countries should be blamed for this problem
72.It can be inferred from the last paragraph that _______.
A. China has hidden a large amount of e-waste in many secret places
B. China has greatly changed the idea about the problem of e-waste
C. China has prevented poisonous materials from entering China for a long time
D. China is falling behind other countries in dealing with e-waste
73.The passage mainly tells us that _______.
A. developing countries are facing serious environmental problems
B. e-waste is a growing problem in developed countries
C. e-waste is sent to developing countries under the excuse of reuse
D. developing countries are making full use of e-waste

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1.解析:,故选A。

2.解析:抽取回族学生人数是,故选B。

3.解析:由,得,此时,所以,,故选C。

4.解析:∵,∴,∴,故选C。

5.解析:设公差为,由题意得,,解得,故选C。

6.解析:∵双曲线的右焦点到一条渐近线的距离等于焦距的,∴,又∵,∴,∴双曲线的渐近线方程是,故选D.

7.解析:∵为正实数,∴,∴;由均值不等式得恒成立,,故②不恒成立,又因为函数是增函数,∴,故恒成立的不等式是①③④。故选C.

8.解析:∵,∴在区间上恒成立,即在区间上恒成立,∴,故选D。

9.解析:∵

,∴此函数的最小正周期是,故选C。

10.解析:如图,∵正三角形的边长为,∴,∴,又∵,∴,故选D。

11.解析:∵在区间上是增函数且,∴其反函数在区间上是增函数,∴,故选A

12.解析:如图,①当时,圆面被分成2块,涂色方法有20种;②当时,圆面被分成3块,涂色方法有60种;

③当时,圆面被分成4块,涂色方法有120种,所以m的取值范围是,故选A。

13.解析:将代入结果为,∴时,表示直线右侧区域,反之,若表示直线右侧区域,则,∴是充分不必要条件。

学科网(Zxxk.Com)14.解析:∵,∴时,,又时,满足上式,因此,

学科网(Zxxk.Com)15.解析:设正四面体的棱长为,连,取的中点,连,∵的中点,∴,∴或其补角为所成角,∵,∴,∴,又∵,∴,∴所成角的余弦值为

学科网(Zxxk.Com)16.解析:∵,∴,∵点的准线与轴的交点,由向量的加法法则及抛物线的对称性可知,点为抛物线上关于轴对称的两点且做出图形如右图,其中为点到准线的距离,四边形为菱形,∴,∴,∴,∴,∴,∴向量的夹角为

17.(10分)解析:(Ⅰ)由正弦定理得,,…2分

,………4分

(Ⅱ)∵,∴,∴,………………………6分

又∵,∴,∴,………………………8分

。………………………10分

18.解析:(Ⅰ)∵,∴;……………………理3文4分

(Ⅱ)∵三科会考不合格的概率均为,∴学生甲不能拿到高中毕业证的概率;……………………理6文8分

(Ⅲ)∵每科得A,B的概率分别为,∴学生甲被评为三好学生的概率为。……………………12分

19.(12分)解析:(Ⅰ)∵,∴

 ,,……………3分

(Ⅱ)∵,∴

,∴数列自第2项起是公比为的等比数列,………………………6分

,………………………8分

(Ⅲ)∵,∴,………………10分

。………………………12分

20.解析:(Ⅰ)∵,∴,∵底面,∴,∴平面,∴,又∵平面,∴,∴平面,∴。………………………4分

(Ⅱ)∵平面,∴,∴为二面角的平面角,………………………6分

,∴,又∵平面,∴,∴二面角的正切值的大小为。………………………8分

(Ⅲ)过点,交于点,∵平面,∴在平面内的射影,∴与平面所成的角,………………………10分

学科网(Zxxk.Com),∴,又∵,∴与平面所成的角相等,∴与平面所成角的正切值为。………………………12分

解法2:如图建立空间直角坐标系,(Ⅰ)∵,,∴点的坐标分别是,∴,设,∵平面,∴,∴,取,∴,∴。………………………4分

(Ⅱ)设二面角的大小为,∵平面的法向量是,平面的法向量是,∴,∴,∴二面角的正切值的大小为。………………………8分

(Ⅲ)设与平面所成角的大小为,∵平面的法向量是,∴,∴,∴与平面所成角的正切值为。………………………12分

21.解析:(Ⅰ)设抛物线方程为,将代入方程得

所以抛物线方程为。………………………2分

由题意知椭圆的焦点为

设椭圆的方程为

∵过点,∴,解得,

∴椭圆的方程为。………………………5分

(Ⅱ)设的中点为的方程为:

为直径的圆交两点,中点为

,则

  

………………………8分

………………………10分

时,

此时,直线的方程为。………………………12分

22.(12分)解析:(Ⅰ)∵是偶函数,∴

又∵,………………………2分

得,

时,时,时,;∴时,函数