2ft diameter 3 blade marine type impeller was used in a 6ft diameter unbaffled tank to stir fuel oil with a viscosity of 5260cP and density of 54lb/ft3. Elevation of liquid, elevation of impeller and stirrer speed were 6ft, 2ft and 4rpm, respectively. If the required force for stirring was measured as 922N, where the torque arm length was 0.11m, calculate the required experimental power