单选题A pump is said to have "negative suction head" when the pump is located （）.Abetween the suction and dischargeBbelow the liquid supplyCabove the liquid supplyDany of the above
单选题
A pump is said to have "negative suction head" when the pump is located （）.
A
between the suction and discharge
B
below the liquid supply
C
above the liquid supply
D
any of the above
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