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问题 解答题

王老师原计划买8只单价为46元的卷笔刀作为奖品，后来决定买4只卷笔刀，用省下的钱再买单价为4元的活动铅笔，可以买活动铅笔多少支？

答案

46×（8-4）÷4，

=46×4÷4，

=46（只）；

答：可以买活动铅笔46支．

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.

 

第（18）空应选择（）

A．controls

B．enemies

C．choices

D．means
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单项选择题

设备进场后，监理工程师应组织设备安装单位在规定的时间内进行检查验收，此时（）应派人参加。

A．供货单位

B．制造单位

C．建设单位

D．A或B
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