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单选题
Which of the following statements is true concerning the overall efficiency of air compressors?（）
A
High pressure compressors are more efficient than low pressure compressors
B
Mechanical efficiency divided by compressor efficiency will equal the overall efficiency of the compressor unit
C
Two stage compressors are generally more efficient than single stage compressors
D
The volumetric efficiency is decreased in multistage compressors
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更多 “单选题Which of the following statements is true concerning the overall efficiency of air compressors?（）A High pressure compressors are more efficient than low pressure compressorsB Mechanical efficiency divided by compressor efficiency will equal the overall efficiency of the compressor unitC Two stage compressors are generally more efficient than single stage compressorsD The volumetric efficiency is decreased in multistage compressors” 相关考题
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