A. 100 ppm
B. 200 ppm
C. 300 ppm
D. 400 ppm
Related Mcqs:
- The relative stability of a sewage sample, whose dissolved oxygen is same as the total oxygen required to satisfy BOD, is______________?
A. 1
B. 100
C. infinite
D. zero - The correct relation between theoretical oxygen demand (TOD), Biochemical oxygen demand (BOD) and Chemical oxygen demand (COD) is given by_______________?
A. TOD>BOD>COD
B. TOD>COD>BOD
C. BOD>COD>TOD
D. COD>BOD>TOD - If Biochemical oxygen demand (BOD. of a town is 20000 kg/day and BOD per capita per day is 0.05 kg, then population equivalent of town is_________________?
A. 1000
B. 4000
C. 100000
D. 400000 - The ratio of 5 day BOD to ultimate BOD is about_______________?
A. 1/3
B. 2/3
C. 3/4
D. 1.0 - The dissolved oxygen level in natural unpolluted waters at normal temperature is found to be of the order of________________?
A. 1 mg/litre
B. 10 mg/litre
C. 100 mg/litre
D. 1000 mg/litre - Dissolved oxygen in streams is______________?
A. maximum at noon
B. minimum at noon
C. maximum at midnight
D. same throughout the day - The minimum dissolved oxygen which should always be present in water in order to save the aquatic life is______________?
A. 1 ppm
B. 4 ppm
C. 10 ppm
D. 40 ppm - 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) - The rate of BOD exerted at any time is_____________?
A. directly proportional to BOD satisfied
B. directly proportional to BOD remain-ing
C. inversely proportional to BOD satisfied
D. inversely proportional to BOD re-maining - The maximum efficiency of BOD removal is achieved in______________?
A. oxidation pond
B. oxidation ditch
C. aerated lagoons
D. trickling filters
