b$)$ A square foundation was planned to be constructed to support a residential building's gross mass of $40000kg$ as shown in Figure Q$3$b$.$ Determine the size of the footing $($B$)$ using a safety factor of $3.$ Refer Appendix $1$ to obtain the Terzaghi's bearing capacity factors.

$4$

$=1880$

${}^{\text{'}}=36$

$c^{\text{'}}=0$