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单选题
If the compression ratio is increased on any diesel engine, （）
A
the expansion ratio will decrease
B
combustion will be slowed down
C
thermal efficiency will decrease
D
thermal efficiency will increase
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单选题For a given fuel, a change in the compression ratio will affect the ignition lag by which of the listed means?（）A
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单选题A two-stroke/cycle diesel engine requires less starting air than a four-stroke/cycle diesel engine, of equal displacement, because the two-stroke/cycle diesel engine（）A
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单选题Which of the following relationships should occur between the temperature developed in a combustion space, and the compression ratio of the engine?（）A
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