A 150m long, 15cm diameter cast iron pipe discharging at elevation 6m higher than the oil surface in the tank. If the oil has kinematic viscosity of 2.1(10)-6 m2/s and specific gravity of 0.84, what...

A 150m long, 15cm diameter cast iron pipe discharging at elevation 6m higher than the oil surface in the tank. If the oil has kinematic viscosity of 2.1(10)-6 m2/s and specific gravity of 0.84, what is the pressure on the oil surface in order to cause a flow rate of 13lps in the pipe? Use relative roughness Ɛ=0.26mm.