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问题 解答题

圆的周长是直径的______倍；或是半径的______倍．如果用C表示圆的周长，那么C=______  或C=______．

答案

圆的周长是直径的 π倍；或是半径的 2π倍．如果用C表示圆的周长，那么C=πd  或C=2πr．

故答案为：π，2π；π的，2πr．

填空题

根据短文大意选择单词并用其正确形式填入空白处,使补全后的短文意思通顺,语法正确,结构完整.（5分）

walk      way     without     prevent     easy

Trees are useful in three important    1  .The most important way is that they  provide man with food , wood and other products. Trees provide food not only for man, but also for animals.  2   trees, many animals could not live on the earth. It’s not    3  for man to live on the earth, either.

The second important way is that trees give us shade(树荫). On a hot summer day, people are eager to have a rest under the shade of a tree after   4  a long way. You can imagine how important the shade of a tree is to man and animals.

The third important way is that trees help to   5   droughts and flood. However, in many parts of the world, man hasn’t realized it. He has cut trees down in large numbers. In the end, he finds that he has lost the best friends he had.
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单项选择题

有一颅底骨折病人，哪项是正确的

A．血性脑脊液病人；腰穿放脑脊液

B．脑脊液耳漏，需尽早修补硬膜漏口

C．伤后视力减退，超过1个月可手术减压

D．颅底骨折需手术治疗以便神经减压

E．着重观察有无脑损伤，并处理脑脊液漏、脑神经损伤等
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