3. Izzard formula for the time of concentration in minutes for the plots having no channels, is (where Lo is the length of overland flow in metres and Kp rainfall intensity in cm/hour)
10. In estimating the rate of evaporation from the reservoir surface, a pan 1.5 metres in diameter, was filled upto 8.0 cm. During a specified period of time, the rainfall recorded was 5 cm. 3 cm of water was removed from the pan to keep the depth of water. At the end of the time, the depth was 9 cm. If the pan coefficient is 0.6, the evaporation loss is