Problem $4$:

For the rainfall event shown below, find the runoff$/$rainfall excess $($a$)$ in the second and fourth intervals, $($b$)$ at the end of the rainfall event, and $($c$)$ in every interval. The soil in the area is saturated. It is an urban, developing areas and the hydrologic soil group is A$.[10]$

Hint: First determine the CN value, remembering that it is for the average condition. Next determine CN value for the condition given. Now follow the class problem.

Time $($min$)0-3030-5050-7070-100100-120120-150$

Rainfall $($in$/$hr$)0\mathrm{.}100\mathrm{.}221\mathrm{.}201\mathrm{.}601\mathrm{.}300\mathrm{.}70$