单选题In a single acting, two-stroke/cycle, diesel generator engine, the power impulse in an individual cylinder occurs （）Aonce every crankshaft revolutionBonce every two crankshaft revolutionsConce every piston strokeDtwice every piston stoke
单选题
In a single acting, two-stroke/cycle, diesel generator engine, the power impulse in an individual cylinder occurs （）
A
once every crankshaft revolution
B
once every two crankshaft revolutions
C
once every piston stroke
D
twice every piston stoke
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