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單項選擇題

What type of valve is used to direct the flow of hydraulic fluid?（）

A.Relief valve
B.Direction control valve
C.Stop valve
D.Pressure control valve

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單項選擇題

The rotor of the hydraulic motor rotates at a speed proportional to the （）.

A.flow of oil
B.pressure of oil
C.A and B
D.temperature of oil

單項選擇題

（） are used to limit the pressure in any particular portion and mainly control the pressure after the valve.

A.Relief valves
B.Check valves
C.Safety valves
D.Reducing valve