Problem $1$

The section HSS $128\frac{3}{16}$ was selected for the column shown below. The base is fixed and the top is pinned. Table $4-3$ in AISC Manual shows that the available compressive strength for the selected section $)=(50$ksi is about $166$kips $?$ Verify the available strength value of the section $($i$.$e$.,166$kips $)$ by hand calculations. Use AISC$/$LRFD specifications. Use $F_y=50$ksi and $F_u=58$ksi.