In its natural condition, a soil sample has a mass of 1.980 kg and a volume of 0.001 m³. After being completely dried in an oven, the mass of the sample is 1.800 kg. Specific gravity G is 2.7. Unit weight of water is 10 kN/m³. The degree of saturation of soil is

A 1-hour rainfall of 10 cm has a return period of 50 years. The probability that 1 hour of rainfall 10 cm or more will occur in each of two successive years is

An isohyet is a line joining points of

The transplantation of rice requires 10 days and total depth of water required during transplantation is 48 cm. During transplantation, there is an effective rainfall (useful for irrigation) of 8 cm. The duty of irrigation water (in hectare/ cumec) is: