323. Surge tanks are used
A. for storage water
B. to increase the velocity in a pipeline
C. as overflow valves
D. to guard against water hammer.
324. Turbidity of water is expressed
A. in ppm
B. in numbers in an arbitrary scale
C. by pH value
D. by colour code.
A. helps growth of bacterias
B. impedes growth of algae
C. increases dissolved oxygen content
D. reduces turbidity.
326. Rapid sand filter
A. should be preceeded by coagulation and sedimentation
B. uses rapid sand as filter media
C. is used after slow sand filtering has been done
D. can combine disinfection also.
327. The four major water supply distribution systems, are
A. dead end, tree, grid iron and reticulation
B. dead end, tree, grid iron and circular
C. tree, grid iron, ring and radial
D. tree, reticulation, circular and ring.
328. Time of concentration
A. is the time taken, for precipitation
B. duration of rainfall.
C. time taken for all the run off to reach the drain
D. time taken for the storm water to travel from the most remote point to the drain.
329. The diameter of pipes in bath rooms and lavatories in domestic water supply, is
A. 6 mm
B. 12 mm
C. 18 mm
D. 24 mm.
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