单选题The discharge rate or capacity of a centrifugal pump will vary directly as the （）.Achange in the impeller diameterBsquare of the impeller radiusCcube of the impeller diameterDimpeller efficiency for large changes in its size
单选题
The discharge rate or capacity of a centrifugal pump will vary directly as the （）.
A
change in the impeller diameter
B
square of the impeller radius
C
cube of the impeller diameter
D
impeller efficiency for large changes in its size
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