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單項(xiàng)選擇題

A mixed-flow pump is a （） pump classified by the working principle.

A.self priming
B.positive displacement
C.reciprocating
D.impeller

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單項(xiàng)選擇題

The （）pump is usually used as the bilge feed pump to an oily water separator.

A.turbine
B.screw
C.vane
D.ejector

單項(xiàng)選擇題

The （）pump is usually used as the emergency bilge pump.

A.turbine
B.screw
C.vane
D.ejector