Facultative bacteria are able to work in________________?

Related Mcqs:

1. In facultative stabilization pond, the sewage is treated by________________?

   A. aerobic bacteria only
   B. algae only
   C. dual action of aerobic bacteria and anaerobic bacteria
   D. sedimentation

2. Assertion A: Slow sand filters are more efficient in removal of bacteria than rapid sand filters. Reason R : The sand used in slow sand filters is finer than that in rapid sand filters. Select your answer based on the coding system given below?

   A. Both A and R are true and R is the correct explanation of A
   B. Both A and R are true but R is not the correct explanation of A
   C. A is true but R is false
   D. A is false but R is true

3. Most of the bacteria in sewage are______________?

   A. parasitic
   B. saprophytic
   C. pathogenic
   D. anaerobic

4. The amount of residual chlorine left in public water supply for safety against pathogenic bacteria is about______________?

   A. 0.01 to 0.05 ppm
   B. 0.05 to 0.5 ppm
   C. 0.5 to 1.0 ppm
   D. 1.0 to 5.0 ppm

5. If the coliform bacteria is present in a sample of water, then the coliform test to be conducted is_____________?

   1) presumptive coliform test
   2) confirmed coliform test
   3) completed coliform test
   The correct answer is ?

   A. only (1)
   B. both (1) and (2)
   C. both (1) and (3)
   D. all (1), (2) and (3)

6. The type of valve, which is provided on the suction pipe in a tube-well, is____________?

   A. air relief valve
   B. reflux valve
   C. pressure relief valve
   D. sluice valve

7. The detention period and overflow rate respectively for plain sedimentation as compared to sedimentation with coagulation are generally_______________?

   A. less and more
   B. less and less
   C. more and less
   D. more and more

8. Scour valves are provided ______________?

   A. at street corners to control the flow of water
   B. at every depression and dead ends to drain out the waste water that may collect there
   C. at the foot of rising main along the slope to prevent back running of water
   D. at every summit of rising mains

9. A sewer that receives the discharge of a number of house sewers is called________________?

   A. house sewer
   B. lateral sewer
   C. intercepting sewer
   D. submain sewer

10. Which of the following values of pH represents a stronger acid?

    A. 2
    B. 5
    C. 7
    D. 10