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單項(xiàng)選擇題

Which of the following will be the advantage of a centrifugal pump as compared with a reciprocating pump?（）
(1) Its discharge is continuous
(2) It has no internal valves
(3) Upon accidental closing of discharge valve, excessive pressure will not build up

A.（1），（2）
B.（2），（3）
C.（1），（2），（3）
D.（2）only

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單項(xiàng)選擇題

The pipe friction and the resistance will （） as a result of an increase in the amount of fluid flowing through the system.

A.reduce
B.rise
C.raise
D.fall

單項(xiàng)選擇題

Air chambers are usually fitted to reciprocating pumps in order to （）.

A.increase discharge pressure
B.increase suction vacuum
C.develop pulsation flow
D.keep a steady rate of flow

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