1. Which one of the following sewage treatment units has parshall flume?
[A] Grit chamber
[B] Trickling filter
[C] Aerated lagoon
[D] Oxidation ditch
Answer: Option A
2. Which one of the following solid waste disposal methods is ecologically most acceptable?
[A] Pyrolysis
[B] Composting
[C] Sanitary landfill
[D] Incineration
Answer: Option B
3. Electrostatic precipitators are used for removal of _____.
[A] Liquid contaminants
[B] Gaseous contaminants
[C] Particulate contaminants
[D] Both A and B
Answer: Option C
4. What is the depth of water seal in the traps?
[A] 7.5 cm to 12.5 cm
[B] < 2.5 cm
[C] Not less than 15 cm
[D] 2.5cm to 7.5 cm
Answer: Option D
5. Sewage treatment in an oxidation pond is accomplished primarily by _____.
[A] Chemical oxidation
[B] Algal photosynthesis
[C] Algal-bacterial symbiosis
[D] Bacterial Oxidation
Answer: Option C