Example $14\mathrm{.}9$: A square footing, $1\mathrm{.}8m1\mathrm{.}8m,$ is placed over loose sand of density $16k\frac{N}{m^3}$

and at a depth of $0\mathrm{.}8$ m $.$ The angle of shearing resistance is $30.N_c=30\mathrm{.}14,N_q=18\mathrm{.}4,$ and

$N_{}=15\mathrm{.}1.$ Determine the total load that can be carried by the footing.