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单选题
In a vapor compression refrigeration the evaporating pressure is maintained constant by the action of the （）, which removes vapor from the evaporator at the same rate at which it is formed.
A
evaporator
B
compressor
C
condenser
D
none of the above
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考题
单选题What is the substance called which can readily be converted from a liquid into a vapor, and also from a vapor into liquid with a reasonably narrow range of pressure?（）A
RefrigeratorB
RefrigerantC
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The BZIP2 compression algorithm consumes more CPU resources than the ZLIB compression algorithm.B
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