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單項(xiàng)選擇題

The reciprocating pump can’t draw water from a tank may be caused by （）.

A.leaky pipe
B.opened inlet valve
C.too much water in tank
D.None of the above

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單項(xiàng)選擇題

（）sometimes called filter, is a device designed to prevent the passage of unwanted solids into the system.

A.Steam trap
B.Check valve
C.Separator
D.Strainer

單項(xiàng)選擇題

Hydraulic pumps most commonly used in steering systems are of the （）.

A.lobe type
B.screw type
C.axial piston type
D.volute type

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