单项选择题

泵站的电磁性噪声的来源主要是( )。

A.变压器
B.空压机
C.轴承振动
D.鼓风机

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问答题

为了纪念那些勇敢的消防战士，一部电影即将开拍。(memory)

填空题

根据下面资料，回答{TSE}题 The first walk into outer space was taken by a Soviet astronaut. Astronaut Zhai Zhigang became the first Chinese to walk in space on September 27,2008. It showed that it was quite safe for a man to be outside the spaceship for a certain period of time. But to walk in space, astronauts have to meet with many kinds of difficulties and dangers. The spaceship goes round the earth at an altitude (海拔高度) of about 200 kilometers above its surface. At such altitude there is no atmosphere which protects the life on the earth. The conditions of outer space are very harmful to man. The boiling point of liquids (液体) goes down with pressure. But pressure outside the spaceship is nearly zero. In such conditions the decompression (减压) of the spacesuit may cause the boiling of the blood and quick death. There is radiation from space and it is harmful. Breathing problems in space can be solved with the help of the spacesuit. Another problem is heat. Man gives off heat in. the course (过程) of his activity, and the harder the labor (劳动) is, the greater the amount (总量) of heat is. In space unless special measures are taken, the heat inside the spacesuit would make the conditions difficult. {TS}根据短文内容．完成下面的句子。(每空一词)(3分) Zhai Zhigang became the first Chinese astronaut__________ __________in space on September 27,2008.

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