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A 4 MGD WWTP discharges a accessory advised arising into a accepting stream. The wastewater has the afterward characteristics: BOD5= 20 mg/L DO = 2.0 mg/L Water Temperature = 24C The accepting upstream from the point of acquittal has the afterward characteristics: Flowrate = 18 cfs BOD5= 4 mg/L DO= 6 mg/L Water Temperature = 27C Cross-sectional Area = 36 sqft a. 3.2 b. 5.2 c. 7.2 d. 8.4 The reaeration amount is estimated to be 0.4 1/day. (Base e at 20C), and the temperature alteration accessory is 1.024. the deoxygenation rate constant is estimated to be 0.23 1/day. (Base e at 20C) and the temperature alteration accessory is 1.047. reaeration and deoxygenation are the alone above factors affecting the attenuated oxygen absorption in the beck afterwards bond with wastewater effluent. Assume the time of travel in the beck to ability the best attenuated oxygen arrears is 3 days. The attenuated oxygen arrears (mg/L) at this area downstream from the point of acquittal is best nearly: