A. maximum at noon
B. minimum at noon
C. maximum at midnight
D. same throughout the day
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 - 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 - 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 - In a BOD test, 1.0 ml of raw sewage was diluted to 100 ml and the dissolved oxygen concentration of diluted sample at the beginning was 6 ppm and it was 4 ppm at the end of 5 day incubation at 20°C. The BOD of raw sewage will be___________?
A. 100 ppm
B. 200 ppm
C. 300 ppm
D. 400 ppm - 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 maximum permissible limit for flouride in drinking water is______________?
A. 0.1 mg/litre
B. 1.5 mg/litre
C. 5 mg/litre
D. 10 mg/litre - Alum as a coagulant is found to be most effective when pH range of water is______________?
A. 2 to 4
B. 4 to 6
C. 6 to 8
D. 8 to 10 - The suitable layout of distribution system for a city with roads of rectangular pattern is______________?
A. grid iron system
B. dead end system
C. ring system
D. radial system - Average rate of water consumption perhead per day as per Indian Standard is______________?
A. 100 litres
B. 135 litres
C. 165 litres
D. 200 litres