A BOD test is run using 100ml of treated wastewater mixed with 200 mL of pure water. The initial DO of the mix is 9 mg/L. After 5 days, the DO is 4 mg/L. After 2 weeks the DO has stabilized at 2.0mg/L.

1. What is the five day BOD₅ of the wastewater?

2. What is the ultimate BOD?

3. What would be the remaining BOD after five days have elapsed?

4. Estimate the BOD reaction rake constant k in (days)

5. Sketch the functions L(t) and B(t) for the bottle for (0 t 20 d).