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單項選擇題

The discharge flow of a reciprocating pump is （）.

A.steady
B.in pulsation
C.continuous
D.large

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單項選擇題

A centrifugal pump produces the required pressure energy by means of a rotating （） provided with vanes.

A.propeller
B.impeller
C.circumference
D.screw

單項選擇題

The pressure head of a pump is given in the unit of （）.

A.kg
B.MPa
C.meter fluid column
D.None of the above is true