A BOD analysis is begun on Monday. 40 mL of waste with DO=0 is mixed with 260 mL of dilution water with a DO of 10 mL. The sample is then put in the incubator. Since the 5th day falls on Saturday, and lab personnel do not work on Saturday, the final DO does not get measured until Monday, the 7th day. The final DO is measured at 3.5 mg/L. However it is discovered that the incubator was set at 30 Celcius. Assume that k1 = 0.2/day at 20 Celcius and that θ = 1.047. Determine the BOD5 at 20 Celcius of the waste.

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