2196Civil EngineeringMedium
3.0 ml of raw sewage is diluted to 300 ml. The D.O. concentration of the diluted sample at the beginning of the test was 8 mg/l. After 5 day-incubation at 20°C, the D.O. concentration was 5 mg/l. The BOD of raw sewerage is________?
A300 mg/l
B200 mg/l
C400 mg/l
D100 mg/l
Correct answer
A. 300 mg/l
Explanation
The correct answer is 300 mg/l.