A footing $2\mathrm{.}5\backslash$times $2\mathrm{.}5$ m is located at a depth of $3\mathrm{.}0$ m in a sand. The internal friction angle is $37\backslash$deg $.$ For $=38\backslash$deg :

$-$ Nq $=67,$ N$\backslash$gamma $=49.$

$-$ Saturated unit weight $\backslash$gamma $\_$sat $=22$ kN$/$m$^3.$

$-$ Unit weight of water $\backslash$gamma $\_$w $=10$ kN$/$m$^3.$

$-$ Natural unit weight $\backslash$gamma $=18$ kN$/$m$^3.$

The bearing capacity equation is given as:

q$\_$ult $=\backslash$gamma D Nq $+0\mathrm{.}4$ B $\backslash$gamma N$\backslash$gamma

a$)$ Determine the allowable bearing capacity if the groundwater table is at a depth of $3\mathrm{.}0$ m$.$

b$)$ Determine the allowable bearing capacity if there is groundwater level at the top.