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單項選擇題

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

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單項選擇題

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

單項選擇題

Overload protection on hydraulic system is provided by the use of （）.

A.stop valves
B.pressure relief valves
C.balance valves
D.regulating speed valves