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單項選擇題

If a centrifugal bilge pump were continually operated with the discharge valve closed the （）.

A.motor overload would open
B.relief valve would open
C.pump would eventually overheat
D.motor would overheat

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單項選擇題

In order to accurately measure very low pressures, which of the instruments listed should be used?（）

A.Compound gage
B.Bonrdon tube
C.Manometer
D.Deadweight gage

單項選擇題

Reduced capacity, accompanied by vibration and noise at the suction of a centrifugal pump is a result of （）.

A.cavitation
B.water hammer
C.fluid friction
D.steam knock