A square foundation is $2m2m$ in plan. The soil supporting the foundation has a friction angle of $=250$ and $c=20k\frac{N}{m^2}.$ The unit weight of soil is $16\mathrm{.}5k\frac{N}{m^3}.$ Determine the allowable gross load on the foundation using Terzaghi Bearing Capacity Equations with a factor of safety $($FS$)$ of $3.$ Assume that the depth of the foundation $($Df$)$ is $1\mathrm{.}5m$ and that general shear failure occurs in the soil. $(15$ pts$)$

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