Q$5)$ A ditch having a cross$-$sectional area of $50sqft(4\mathrm{.}6m^2)$ is being excavated in

common earth. The soil's angle of repose is $35$ and its swell is $25\%.$ Find the height

and base width of the triangular spoil bank that will result from the excavation.

$($Assume that the length is $16\mathrm{.}40ft(5m).)$