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單項(xiàng)選擇題

Which of the following statements about pump operations is NOT a correct statement?()

A.In order for a fluid to be pumped, a fluid must be made to flow
B.A substance must be cold in order for it to be pumped
C.The kinetic energy imparted by the pump can be used to force a liquid through a hydraulic system
D.A pump must receive its energy from an external source

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