$(6-31)$ The figure shows the free$-$body diagram of a connecting$-$link portion having stress concentration at three sections. The dimensions are $r=0\mathrm{.}25in,d=0\mathrm{.}40in,h=0\mathrm{.}50in,w_1=2\mathrm{.}5in,$ and $w_2=1\mathrm{.}5in.$ The forces $F$ fluctuate between a tension of $16$ kips and a compression of $4$ kips $.$ Neglect column buckling and find the least factor of safety if the material is cold$-$drawn AISI $1018$ steel using the Goodman criterion.