0.25 to 0.35 mm

0.35 to 0.60 mm

0.60 to 1.00 mm

1.00 to 1.80 mm

(i) and (ii)

(ii) and (iii)

(i) and (iv)

(ii) and (iv)

Both A and R are true and R is the correct explanation of A.

Both A and R are true but R is not the correct explanation of A.

A is true but R is false.

A is false but R is true.

excessive negative head

mud ball formation

higher turbidity in the effluent

low temperature

0.2 to 0.4

0.4 to 1.0

2 to 4

5 to 7