A70 percent efficient pump delivers water at 20°c from one reservoir to another 20 ft higher. the piping system consists of 60 ft. of galvanized-iron 2-in pipe, a reentrant entrance, two screwed 90° long-radius elbows, a screw open gate valve, and a sharp what is the input power required in horsepower for a flow rate of 0.4 ft/s.