Given:

W$/14132$

ASTM A$572$ Gr $50$ Steel.

Column length $=18$ ft long and pinned at top and bottom.

Determine:

$1.$ Maximum allowable compressive stress $($Fa$),$ assuming no lateral bracing.

$2.$ Maximum allowable compressive load $($P$),$ assuming no lateral bracing.

$3.$ Maximum allowable compressive stress $($Fa$),$ assuming the column braced at mid height in the week axis.

$4.$ Maximum allowable compressive load $($P$),$

assuming the column braced at mid height in the week axis.

$5.$ Find the lightest W$14$ that can safely carry a load P$=750$ Kips.