The plan of a survey plotted to a scale of 10m to 1cm is reduced in such a way that a line originally 10cm long now measures 9cm. the area of the reduced plan is measured as 81cm2. the actual (m2) of the survey is

The magnetic bearing of a line AB is S 45° E and the declination is 5° west. The true bearing of the line AB is

The water content of a saturated soil and the specific gravity of soil solids were found to be 30% and 2.70, respectively. Assuming the unit weight of water to be 10 $$kN /m^3$$, the saturated unit weight ($$kN /m^3$$), and the void ratio of the soil are

The consumptive use of water for a crop during a particular stage of growth is 2.0mm / day. The maximum depth of available water is the root zone is 60mm. Irrigation is required when the amount of available water is 50% of the maximum available water in the root zone. Frequency of irrigation should be