3. A direct runoff hydrograph due to an isolated storm with an effective rainfall of 2 cm was trapezoidal in shape as shown in the below figure. The hydrograph corresponds to a catchment area (in sq. km) of
10. Which one of the following set of values give the minimum clear cover (in mm) for the main reinforcements in the slab, beam, column and footing, respectively, according to IS : 456-1978?