Find the Norton equivalent network seen by $R_5$ in Eigure P2.68. Use it and current division to compute the current through $R_5$. Assume $R_1=15 \Omega, R_2=8 \Omega$, $R_3=4 \Omega, R_4=4 \Omega, R_5=2 \Omega, I 1=2 \mathrm{~A}, I 2=3 \mathrm{~A}$.