starch iodide method

orthotolidine method

both starch iodide method and orthotolidine method

none of the above

ultra violet rays treatment

lime treatment

by using potassium permanganate

chlorination

less than 1.0 m/sec

1.0 m/sec to 1.2 m/sec

1.5 m/sec to 2.0 m/sec

3.0 m/sec to 3.5 m/sec