Question

The Streeter-Phelp's oxygen sag equation for a river is based on a few assumptions. The correct assumption(s) is/are

• A. At any instant the deoxygenation rate is directly proportional to the amount of oxidizable organic material present.
• B. At any instant the deoxygenation rate is inversely proportional to the amount of oxidizable organic material present.
• C. The reoxygenation rate is directly proportional to the dissolved oxygen deficit.
• D. The reoxygenation rate and deoxygenation rate are directly proportional to the saturation concentration of dissolved oxygen.

Answer 1

Answer: (A), (C)

At any instant the deoxygenation rate is directly proportional to the amount of oxidizable organic material present.

Answer 2

The correct answer is (A and C) : At any instant the deoxygenation rate is directly proportional to the amount of oxidizable organic material present. AND The reoxygenation rate is directly proportional to the dissolved oxygen deficit.