1.2 cm 40m Hot Water tank In large buildings, hot water in a water tank is circulated through a loop so that the user doesn't have to wait for all the water in long piping to drain before hot water starts coming out. A certain recirculating loop involves 40-m-long, 1.2-cm-diameter cast iron ( = 0. 00026 m) pipes with six 90 threaded smooth bends (K = 0.9 each) and two fully open gate valves (K = 0.2 each). Take the average flow velocity through the loop to be 2 m/s, the average water temperature to be 60C (p = 983 kg/m, = 4.67 x 104 kg/ms) and the efficiency of the pump to be 60%. Determine the required power input for the recirculating pump. (Note: the loss coefficients at the entrance and exit are ignored) W