Find the power required to drive a centrifugal pump which delivers 0.04 m^{3}/s of water to a height of 20 m through a 15 cm diameter, 100 m long pipe. The overall efficiency of the pump is 70 % and the co-efficient of friction f = 0.015 in the formula h_{f} = 4fLV^{2}/(2gd). (answer in kW)