Problem $1$

Select the lightest $28ft$ long $W12$ available to

support a factored tensile load of $P_u=400k.$

Assume there are $2$ lines, $($lines are $5"$ apart$)$ of

$\frac{7}{8}"$ bolts in each flange $(4$ lines total$)$ and $3$ bolts

per line @ $4"$ o$.$c$.$ and $4"$ to end. Assume A$992$

steel. Dimensions are from centers of bolt holes.