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问题 单项选择题

如图所示的正方形的边长为10，AB与正方形的底边垂直，那么图中阴影部分的面积是（）。

A．80

B．60

C．50

D．40

答案

参考答案：C

解析：

如下图，△EFG的面积=矩形ABEF面积的，△CDH的面积=矩形ABCD面积的，即△EFG的面积+△cDH的面积=正方形CDFE面积的，所以，阴影部分的面积占整个图形面积的，即10×10÷2=50。

 

单项选择题

It is clear that some chemicals can damage the health of animals and humans. (1) , this is not the only problem that (2) be caused by the careless use of chemicals. Chemicals can also (3) the ecological balance of the environment. If the ecological balance is disturbed, the results can be (4) serious.

The (5) of DDT illustrates the problem. DDT, a chemical which kills insects, at first seemed to be a perfect answer (6) many problems. It would control insects that caused dangerous diseases, (7) insects that caused billions of dollars of damage to crops every year. Governments permitted and even (8) the use of DDT. Farmers in many countries (9) to spray it on their crops. The (10) results were good: Damage to crops (11) down, and profits went up. However, the chemical had effects which the scientists didn’t see in (12) . First, it also killed insects which were the (13) enemies of the harmful insects and which were therefore beneficial to farmers. Second, and perhaps worse, DDT did not kill (14) harmful insect. A few insects had natural resistance to the chemical. They (15) and reproduced in large numbers. In a few years there were large numbers of insects which were not (16) by DDT, and there were (17) insects which could act as natural (18) on these new "super-insects". Finally, it became clear that DDT was not solving the insect problem. In fact, it was making the problem worse. It (19) became necessary to find a second (20) for the effects of the first.

7（）

A.as well as 

B.as well 

C.but 

D.also
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单项选择题

地方各级人民政府的行政编制总额必须报（）批准。

A.地方人民政府

B.国务院

C.国务院机构编制管理机关

D.地方人大常委会
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