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A completely mixed activated-sludge plan is being designed for a wastewater flow of 3.0 mgd. The BOD of 225 mg/l is 200 mg/l soluble. The effluent soluble BOD requirement is 7 mg/l (70 percent of the total 10 mg/l). For sizing, the mean cell residence time is to be 8 days at an MLSS of 2500 mg/l. Laboratory analysis resulted in Y=0.6 lb VSS/lb BOD, Kd=0.06 per day, K=5.0 per day, and Ks=60 mg/l. Calculate the aeration basin size (use a saftely factor of two times larger than waht is calculated) and he wate sludge rate.