During propane reforming of hydrogen sulphide, suppose that two cracking reactions occur in a steady$-$flow reactor:

$6H_{2}S+C_3{H}_8$harr$3C{S}_2+10H_2$

$C_3{H}_{8}harr{C}_3{H}_6+H_2$

$($a$)$ Plot the effect of temperature $(400$ to $1000C)$ on the Gibbs energy and equilibrium constant $(lnK)$ at a pressure of $1\mathrm{.}2$ bars