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單項選擇題

A simple pumping system consists of a suction branch, a pump and （）.

A.a priming device
B.a discharge branch
C.a filter
D.a suction valve

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單項選擇題

A(n) （） is a device which adds to the energy of a liquid or gas causing an increase in its pressure and a movement of the fluid.

A.pump
B.engine
C.turbine
D.boiler

單項選擇題

Lubricating oil systems are fitted with a wide variety of strainers some of which can be cleaned in site while others have replaceable cartridgesThe bold and italic word “which” means （）.

A.lubricating oil
B.lubricating oil systems
C.strainers
D.cartridges

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