$17-4$ to $17-6.$ Using the appropriate AISC equations, determine ${}_c{P}_n$ and $\frac{P_n}{{}_c}$ for each of the

given sections, which are filled with $145l\frac{b}{f}{t}^3$ concrete.

$17-4.$ An HSS $1616\frac{1}{2},F_y=50$ksi,$f_c^{\text{'}}=4$ksi, and $(KL{)}_x=(KL{)}_y=14ft.$

$17-5.$ An HSS $1410\frac{1}{2},F_y=50$ksi,$f_c^{\text{'}}=4$ksi, and $(KL{)}_x=(KL{)}_y=12ft.$

$($Ans$.981\mathrm{.}5k,654\mathrm{.}3k)$