单选题Operating a rotary pump at speeds in excess of design requirements could cause（）.Adecreased clearances between rotating partsBdecreased slippage to the suction side of the pumpCair binding in the discharge portsDerosion and excessive wear
单选题
Operating a rotary pump at speeds in excess of design requirements could cause（）.
A
decreased clearances between rotating parts
B
decreased slippage to the suction side of the pump
C
air binding in the discharge ports
D
erosion and excessive wear
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