Ag runoff discharges into a small river. The runoff has the following characteristics:Flow (Q) = 100 m³ /min; D0 =3 mg/L; BOD = 150 mg/L The river flows at 1,000 m³/min, has no BOD, and 9 mg/L DO. given the saturation for DO is 9.5 mg/L and the ka is 0.4 day , and ka is 0.7 day1, calculate the DO and BOD remaining downstream 1.5 days after the discharge event.

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