URGENT HELP IS NEEDED THX$!!$

SHOW ALL WORK $/$ STEPS

Two$-$port networks N$1$ and N$2$ are connected in series. The parameters for each network are as follows:

N$1$: $Z_1=\left[\begin{array}{cc}5& 3\\ 3& 6\end{array}\right],N2$:$Z_2=\left[\begin{array}{cc}2& 1\\ 1& 3\end{array}\right].$

Find the Z$-$parameters for the overall network $($total Z$-$parameters$)$