28) According to Atterberg, the soil is said to be of medium plasticity if the plasticity index PI is

29) If the natural water content of soil mass lies between its liquid limit and plastic limit, the soil mass is said to be in

30) When the plastic limit of a soil is greater than the liquid limit, then the plasticity index is reported as

31) Toughness index is defined as the ratio of

32) If the plasticity index of a soil mass is zero, the soil is