A flat plate $\frac{1}{2}$ in$.$ thick is subjected to an axial force $P$ of $40$ kips, as shown. The normal and shear stresses on section $m-m$ are most nearly:

${}_{}=11\mathrm{.}55$ksi,$L_Q=6\mathrm{.}67$ksi

${}_{}=15\mathrm{.}42$ksi,$t_{}=8\mathrm{.}33$ksi

${}_0=6\mathrm{.}67$ksi,$t_O=11\mathrm{.}55$ksi

${}_0=8\mathrm{.}33$ksi,$t_0=15\mathrm{.}42$ksi