8.29 Two reservoirs are connected by three clean cast-iron pipes in series, L1 = 600 m, D1 = 0.3 m, L2 = 900 m, D2 = 0.4 m, L3 = 1500 m, and D3 = 0.45 m. The flow rate is 0.11 m3/s of water at 15 C.

Determine the difference in elevation between the reservoirs.