Q$\mathrm{.}4)$ A rectangular plot $($ABCD$)$ forms the plane of a pit excavated for road work. $($E$)$ is point of intersection of the diagonals. Calculate the Volumes of the Barrow$-$Pit from the following data: $-$

$\backslash$table$[[$Point$,$A$,$B$,$C$,$D$,$E$],[$Ground level $($m$),45\mathrm{.}2,49\mathrm{.}8,51\mathrm{.}2,47\mathrm{.}2,52\mathrm{.}0],[$Final level $($m$),38\mathrm{.}6,39\mathrm{.}8,42\mathrm{.}6,40\mathrm{.}8,42\mathrm{.}5]]$

Length of $,$ and $BC=80m$