The suitable layout of a distribution system for irregularly growing town is_______________?

A. Dead end system
B. Grid iron system
C. Radial system
D. Ring system

Activated carbon is used for_____________?

A. Disinfection
B. Removing hardness
C. Removing odours
D. Removing corrosiveness

The major disadvantage of lime soda process of water softening is that_________________?

A. It is unsuitable for turbid and acidic water
B. Huge amount of precipitate is formed which creates a disposal problem
C. The effluent cannot be reduced to zero hardness
D. It is unsuitable for softening the water of excessive hardness

Disinfection efficiency is________________?

A. Reduced at higher ph value of water
B. Unaffected by ph value of water
C. Increased at higher ph value of water
D. Highest at ph value equal to 7

The population of a town in three consecutive years are 5000, 7000 and 8400 respectively. The population of the town in the fourth consecutive year according to geometrical increase method is________________?

A. 9500
B. 9800
C. 10100
D. 10920

In chlorination, with the rise in temperature of water, death rate of bacteria____________?

A. Increases
B. Decreases
C. Remains unaffected
D. None of the above

The suitable method for disinfection of swimming pool water is________________?

A. Ultra violet rays treatment
B. Lime treatment
C. By using potassium permanganate
D. Chlorination

The percentage of chlorine in fresh bleaching powder is about________________?

A. 10 to 15
B. 20 to 25
C. 30 to 35
D. 40 to 50

Chlorine demand of water is equal to________________?

A. Applied chlorine
B. Residual chlorine
C. Sum of applied and residual chlorine
D. Difference of applied and residual chlorine

The rate of Alteration of pressure filters is_________________?

A. Less than that of slow sand filters
B. In between the filtration rate of slow sand filters and rapid sand filters
C. Greater than that of rapid sand filters
D. Equal to that of slow sand filters