Compute four points on the interaction diagram for the column shown in Fig. $11-17$a $.$ Use $f_c^{\text{'}}=5000$ psi and $f_y=60,000.A_g=bh$ is $256in.{?}^2,A_{s1}=4i{n}^2,A_{s2}=4i{n}^2,A_{st}=A_{si}=8in.{?}^2,$ and ${}_g=\frac{A_{st}}{A_g}=0\mathrm{.}031.$ The yield strain, $lo{n}_y=\frac{f_y}{E_s},$ is $60,000\frac{}{29},000,000=0\mathrm{.}00207.$ Use load factors and strength$-$reduction factors from ACI Code Table $21\mathrm{.}2\mathrm{.}2.$

$($a$)$ Section.

$($c$)$ ivorniran suesses.