Question: When operated at 1170 rpm, a centrifugal pump, with impeller diameter of 8 in., has a shut-off head of 25.0 ft of water. At the same operating speed, best efficiency occurs at 300 gpm, where the head is 21.9 ft of water. Specify the discharge and head for the pump when it is operated at 1750 rpm at both the shut-off and BEPs.