C$8\mathrm{.}1$ The link shown in the figure carries a tensile force $P$ with an offset $d.$ Given

$P,d,$ and the dimensions of the cross section, write an algorithm that computes the

maximum tensile and compressive stresses on section $m-n.($a$)$ Run the algorithm with

the following data: $P=20kN,d=60mm,h=90mm,t_w=11$:$25mm,t=15mm,$

$a=45mm,$ and $b=30mm($b$)$ If the working normal stress is $70$MPa, find by

experimentation the optimal values of a and $b($the values that minimize $a+b),$ the

other data being as in part $($a$).$help