10.15 A centrifugal pump operating at N =2265 rpm lifts water between two reservoirs connected by 300 ft of 6-in.-diameter and 100 ft of 3-in.-diameter cast-iron pipe in series. The gravity lift is 25 ft. Estimate the head requirement, power needed, and hourly cost of electrical energy to pump water at 200 gpm to the higher reservoir.

Assume that electricity costs 12¢ kW hr and that the electric motor efficiency is 85 percent.