Problem 3. A BOD test is run using 100 mL of wastewater and mixed with 200 mL of pure water. The initial DO of the mix is 9.0 mg/L. After

5 days, the DO is 4.0 mg/L. After a long period of time, the DO is 2.0 mg/L and the D0 is no longer changing. Assume nitrification is insignificant (all BOD is carbonaceous). A. What is the BOD5? B. Assuming no nitrification effects, estimate the ultimate carbonaceous BOD. C. What would the BOD remaining be after 5 days? D. Estimate the reaction rate constant k (day')?