$($a$)$ For the system ethylene $(1)/$propylene $(2)$ as a gas, estimate $f_1^n,f_2{?}_2{}^{\text{h}\text{a}\text{t}(1)},$ and hat$({)}_2$ at $T=150C,P=30$ bar, and $y_1=0\mathrm{.}35.$

$($b$)$ If the feed the mixture is changed to $C{O}_2\frac{1}{C}{H}_4(2)$ in part $($a$)$ what would be the effect on the fugacity and fugacity cocfficient?

$($c$)$ If the pressure in part $($a$)$ is increased to $\frac{100}{b}ar,$ what would be the effect on the fugacity coefficient?

$($d$)$ If the temperature in part $($a$)$ is increased to $300C,$ what would be affect on fugacity coefficient.