A fine-bubble aeration basin has a flow of 21.5 mgd, an influent BOD of 180 mg/l, 31 mg/l of mmonia, and effluent of 10 mg/l. During the winter, the wastewater temperature of 14.8 degrees C does not nitrify. During the summer , wastewater temperatures increase to 18.5 degrees C and operators cannot avoid nitirification. The residual DO is controlled to maintain 2.0 mg/l. Diffusers are 15 ft deep. use average oxygen transfer values for (alpha)F and (beta). Calculate (1) winter and (2) summer values for oxygen demand, oxygen tranfer, hp, and airflow rate.