Question $5[20$ points$]$

A$.)$ A column load of $200$ kN is supported via a $3m4m$ footing whose bottom is $1$ m below the surface. Assuming the footing distributes uniform pressure, determine the vertical stress at a depth of $4$ m at a point.

a$.$ Under the center of the footing.

b$.$ Under one of the corners $.$

B$)$ What is Boussinesq's vertical stress at a point $5$ m directly below a concentrated load of $1000$ kN applied at the ground surface?