A completely mixed activated sludge plant treats the wastewater from a dairy production facility. The reactor basin has a volume of 5000m3. Four 120kW surface aerators are used for aeration. The value is 0.9 and is 0.95 . The field measurements show that the oxygen uptake rate under field conditions was 70mg/Lh, and the average operating (required) oxygen concentration in the reactor was 2mg/L. The wastewater temperature was 15C, and the saturation dissolved oxygen concentration was 9.8 mg/L at 15C under field conditions. Hint: C5 at 20C is 9.17mg/L. a) (10 p.) Determine the standard oxygen transfer rate (SOTR) of the aerators in kg/kWh. b) (10 p.) Determine the power input (kW) required per 1000m3 of wastewater treated