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單項(xiàng)選擇題

A variable displacement system of hydraulic drives consists of （）.

A.a variable displacement axial piston pump
B.a constant displacement axial piston pump
C.a reciprocating piston pump
D.a centrifugal pump

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單項(xiàng)選擇題

Which of the following hydraulic systems is not one of the three sub-division of the Hydraulic drive system?（）

A.Constant pressure system
B.Variable pressure system
C.Variable displacement system
D.Constant volume system

單項(xiàng)選擇題

It is important with all hydraulic systems to ensure that interlocking arrangements provided for pump or motor control levers are （） before the pump driving motor can be started.

A.in the pert position
B.in the starboard position
C.in the neutral position
D.to be dismantled