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單項選擇題

In general, （） is suitable for delivering small quantities at high pressure.

A.reciprocating pump
B.gear pump
C.centrifugal pump
D.vane pump

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單項選擇題

In four strokes engine, the cycle of events is completed in four strokes of （）.

A.the cylinder
B.the crankshaft
C.the piston
D.the cross-head

單項選擇題

In each cylinder cover there are two or three holes for （）

A.the exhaust valves
B.the fuel valves
C.indicator cocks
D.the fuel pumps

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