Workout part e and use part c and d if needed, give a numerical answer on paper WRITTEN!

$($c$)$ Net rainfall of $10mm$ in the first hour, $20mm$ in the second hour and $15mm$ in the third hour

falls on catchment $A.$ Calculate the resulting run$-$off as a function of time.

$($d$)$ Net rainfall of $10mm$ in the first hour, $20mm$ in the second hour and $15mm$ in the third hour

falls on catchment B$.$ Calculate the resulting runoff as a function of time.

$($e$)$ The rivers flowing out from catchments A and $B$ meet shortly after they leave the catchments. $A$

storm with the net rainfall given above moves across the two catchments, with the rainfall starting

an hour later on catchment $B$ than catchment $A.$ Calculate the resulting combined run$-$off as a

function of time.