The Newton-Raphson iteration $${x_{n + 1}} = {1 \over 2}\left( {{x_n} + {R \over {{x_n}}}} \right)$$ can be used to compute

A wastewater sample contains $$10^{-5.6}$$ mol/l of OH^- ions at $$25^o$$ C. The pH of this sample is

The type of surveying in which the curvature of the earth is taken into account is called

An outlet irrigates an area of 20 ha. The discharge (lit/sec) required at this outlet to meet the evapotranspiration requirement of 20mm occurring uniformly in 20 days neglecting other field losses is