Find the lightest W section for a tension member made of A57

Find the lightest W section for a tension member made of A572 Grade 50 steel. The axial tension in the member due to dead load is 70 kips due to live load is 10 kips. The connections at the end of the member include 7/8 in diameter bolts, one per line.

Solution

I have solved most of this but I have been given the oppertunity to get extra credit if it\'s 100% correct so I would greatly appreciate some help to ensure I didn\'t veer away from the correct answers.