For the analysis of direct runoff from a hydrograph, the empirical relation N = 0.827 A0.2 is used to find the time base. In this equation, the area 'A' must be expressed in which units?

Which of the following statements (S1, S2, and S3) pertaining to the development of irrigation and its impacts is/are correct? S1: It increases food production. S2: It improves groundwater storage in the irrigated command area through deep percolation. S3: It increases the tendency to adopt mixed cropping.

In border strip flood irrigation, the optimal time of ponding or water application is estimated primarily on the basis of: