$5\mathrm{.}5\mathrm{.}4($a$)$ Compute the runoff from a $7-$in rainfall on a $1500-$acre watershed that has hydrologic soil groups that are $40$ percent group $\backslash ($ A$,40\backslash )$ percent group $\backslash ($ B $\backslash ),$ and $20$ percent group $\backslash ($ C $\backslash )$ interspersed throughout the watershed. The land use is $90$ percent residential area that is $30$ percent impervious, and $10$ percent paved roads with curbs. Assume AMC II conditions.

$($b$)$ What was the runoff for the same watershed and same rainfall before development occurred? The land use prior to development was pasture and range land in poor condition.