1. MPN index is a measure of _____.
[A] BOD
[B] Dissolved Oxygen content
[C] Hardness
[D] Coliform bacteria
Answer: Option A
2. Crown corrosion in a reinforced concrete sewer is caused by _____.
[A] Methane
[B] Carbon Dioxide
[C] Hydrogen Sulphide
[D] Ammonia
Answer: Option C
3. The unit in which both sedimentation and digestion processes of sludge take place simultaneously is ______.
[A] Deritus Tank
[B] Digestion Tank
[C] Imhoff Tank
[D] Skimming Tank
Answer: Option C
4. Which one of the following tests of water/ wastewater employs Eriochrome Black T as an indicator?
[A] DO
[B] Residual chlorine
[C] COD
[D] Hardness
Answer: Option D
5. Presence of nitrogen in a waste sample is due to the decomposition of _____.
[A] Fats
[B] Carbohydrates
[C] Vitamins
[D] Proteins
Answer: Option D