3. A rainfall with intensity of 45 mm/h and duration of 1.5 h falls on a 540 ha catchment. Use rational method to calculate the peak runoff for the followingconditions:

Natural soil, with time of concentration te = 2 hour and C = 0.4, b) Improved, partially paved area, with time of concentration te 1 hour and C 0.7.State any assumptions used.