Water at 20°C is to be pumped from a reservoir (z A = 2 m) to another

Question:

Water at 20°C is to be pumped from a reservoir (z_A= 2 m) to another reservoir at a higher elevation (z_B= 9 m) through two 25-m-long plastic pipes connected in parallel. The diameters of the two pipes are 3 cm and 5 cm. Water is to be pumped by a 68 percent efficient motor€“pump unit that draws 7 kW of electric power during operation. The minor losses and the head loss in the pipes that connect the parallel pipes to the two reservoirs are considered to be negligible. Determine the total flow rate between the reservoirs and the flow rates through each of the parallel pipes.

Reservoir B Ze= 9 m 25 m 3 ст Reservolr A 5 cm ZA= 2 m Pump FIGURE P14-91