Task $1\mathrm{.}4$ Calculate the horizontal and vertical stresses in soil due to additional surface load

A $3012m$ rectangular raft that is $2\mathrm{.}5m$ below the ground's surface is subjected to a $54000kN$ load. Assume that the origin of the coordinates $(0,0)$ is the area's centre. and the coordinates for the corners are $(6,15).$

By using the procedures of

$($a$)$ Boussinesq and

$($b$)$ Westergaard at coordinates of $(0,0),(0,15),(6,0),(6,15),$ and $(10,25),$ determine the stresses at a depth of $20m$ below the foundation level. Likewise, calculate the stresses' ratios based on the results of the two approaches. Don't consider the effect of foundation depth on stresses.