单选题The discharge head of a centrifugal pump will vary directly with the （）.Achange in impeller diameterBsquare of the impeller diameterCcube of the impeller diameterDimpeller efficiency for large changes in the size of the impeller
单选题
The discharge head of a centrifugal pump will vary directly with the （）.
A
change in impeller diameter
B
square of the impeller diameter
C
cube of the impeller diameter
D
impeller efficiency for large changes in the size of the impeller
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