$($IV$)($a$)$ A system has two major process and is controlled with proportional

controller. The transfer function of the process are:

$G_1=\frac{0\mathrm{.}1}{2s+1}$;$G_2=\frac{1}{5s+1}$

Where $G_1$ and $G_2$ are connected in series and time constants are in

minutes. Find the recommended controller gain for a damping coefficient

of $0\mathrm{.}5.$