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问题 填空题

远处传来阵阵锣鼓声，寻声而去，锣鼓声的______不变，但______增大．

答案

锣鼓是通过锣面\鼓面的振动发出声音的；

寻声而去，距离发声体的远近变的过程中，锣鼓振动的频率不变，音调是不变的，响度变大；

故答案为：音调；响度．

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（12）空应选择（）

A．need

B．turn

C．advance

D．vain
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单项选择题

有关对最高额土地抵押权具有一定独立性的叙述中，不正确的是（）。

A.在一般土地抵押权中，土地抵押权完全从属于主债权，随主债权的设立、转移和消灭而设立、转移和消灭

B.最高额土地抵押权的设立、转移和消灭在一定程度上独立于主债权

C.在设立上，没有债权存在，但能设立一般土地抵押权

D.最高额土地抵押权却往往为将来的债权而设，不需要依附于现成的债权
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