Q$3.$ A $1000-ft$ long pipeline requires an excavation $4ft$ wide to an average depth of $3ft.$ If the soil is common earth, moist, and the swell factor for the common earth is $1\mathrm{.}25.$ What size spoil bank will be created by the excavation?

Table $6.$ Typical values of angle of repose of excavated soil

$\backslash$table$[[$Material$,$Angle of Repose $($deg$)],[$Clay$,35],[$Common earth, dry,$32],[$Common earth, moist,$37],[$Gravel$,35],[$Sand$,$ dry,$25],[$Sand$,$ moist,$37]]$

Q$4.$ A rectangular ditch having a cross$-$sectional area of $24sqft$ and an average depth of $7\mathrm{.}5ft$ is being excavated in clay. The soil's angle of repose is $35$ and its swell is $30\%.$ Find the height and width of the conical spoil bank.