The solid $1\mathrm{.}45-$in$.-$diameter rod is subjected to a uniform axial distributed loading along its length of $w=875l\frac{b}{f}t.$ Two concentrated loads also act on the rod: $P=2300lb$ and $Q=900lb.$ Assume $a=15in.$ and $b=30in.$ Determine the normal stress in the rod at the following locations:

$($a$)x=10$ in$.$

$($b$)x=30$ in$.$

Part B ONLY