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单选题
In a four-stroke engine the camshaft rotates at （）.
A
half the engine speed
B
twice the engine speed
C
the engine speed
D
four times the engine speed
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a two-stroke engine can’t work without cylindersB
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考题
单选题In a four-stroke engines the camshaft rotates at （）.A
half the engine rotational speedB
twice the engine rotational speedC
the engine rotational speedD
four times the engine rotational speed
考题
单选题In a four-stroke/cycle diesel engine, the camshaft rotates at （）A
twice the crankshaft speedB
half the crankshaft speedC
the same speed as that of the crankshaftD
a speed independent of that of the crankshaft
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