The ordinates of a 3hr unit hydrograph of a basin at 6 hr interval are given below. You are required to derive the storm hydrograph due to a 3 hr storm with a total rainfall of 15 cm. Assume an initial loss of 0.5 cm and aφindex of 1 cm/ hr.    Take base flow = 2.5 m3/s
Time (hrs)
                                  0              6               12      18     25     30     36    42      48    54     60        
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Unit Hydrograph
m3/s                               0                 3                 5            9        11      7       5       4        2        1        0
Please explain in words and show the calculations you did to  arrive at the solution.