Question #2: (25 points) A catchment area noting that 35 mm of rain fell in a discharge area of 78.2 square kilometers over a period of one hour started at 01:00. The following table shows the measured runoff through the area in the unit of time. Calculate and draw one-hour unit hydrograph Time, hr Measured flow, m3/s Time, hr Measured flow, m3/s 0 0 1 2 3 4 5 6 7 8 9 1 1.2 2.97 24.1 51.5 32.3 11.2 5.95 3.77 10 11 12 13 14 15 16 17 18 2.83 2.38 2.02 1.76 1.64 1.47 1.39 1.27 0 ii. Compute and plot the hydrograph of surface runoff for two periods of heavy rain occurring: First storm: of 85mm rain between midnight and 01-30 hr; and 40mm rain between 02-00 and 03-00 hr. Second storm: of 67mm rain between 04-00 and 05-00 hr. Assume a constant loss rate of 18mm and a constant base flow of 8m/s Comment about your graph. Question #2: (25 points) A catchment area noting that 35 mm of rain fell in a discharge area of 78.2 square kilometers over a period of one hour started at 01:00. The following table shows the measured runoff through the area in the unit of time. Calculate and draw one-hour unit hydrograph Time, hr Measured flow, m3/s Time, hr Measured flow, m3/s 0 0 1 2 3 4 5 6 7 8 9 1 1.2 2.97 24.1 51.5 32.3 11.2 5.95 3.77 10 11 12 13 14 15 16 17 18 2.83 2.38 2.02 1.76 1.64 1.47 1.39 1.27 0 ii. Compute and plot the hydrograph of surface runoff for two periods of heavy rain occurring: First storm: of 85mm rain between midnight and 01-30 hr; and 40mm rain between 02-00 and 03-00 hr. Second storm: of 67mm rain between 04-00 and 05-00 hr. Assume a constant loss rate of 18mm and a constant base flow of 8m/s Comment about your graph