Problem $3(40$ points$)$: The figure shows the LRFD factored $($a$)$ end internal moments $(M_{nt})$ and internal axial force $)$ generated from the vertical gravity load, and $($b$)$ end internal moments $(M_t)$ and internal axial force $(P_{lt})$ generated from the lateral load.

Design Code:

AISC: Steel Construction Manual, ${15}^{th}$ Edition

Design Data:

Column C$1$: ASTM A$992,$ W$10$ x $49,L_c=12ft.,Cb=1$

$\frac{{}_H}{L}=0\mathrm{.}0025$

$P_{mf}=283\mathrm{.}7k$

$P_{\text{s}\text{t}\text{o}\text{r}\text{y}}=283\mathrm{.}7k$

$H=33\mathrm{.}6k$

Assumption:

Use Direct Analysis Method

Un$-$braced moment frame with sway

The LRFD capacity for column $C1$ under axial$-$flexural combined loading is most nearly $($bucu Anaysis ivietnod$)$:

e$)0\mathrm{.}64$

f$)0\mathrm{.}76$

g$)0\mathrm{.}90$

h$)0\mathrm{.}98$