Compute the matrix product A*B of the following pairs of matrices: \text { (a) } A=\left[\begin{array}{cc} 12 & 4 \\ 3 & -5 \end{array}\right] \quad B=\left[\begin{array}{cc} 2 & 12 \\

0 & 0 \end{array}\right] \text { (b) } A=\left[\begin{array}{lll} 1 & 3 & 5 \\ 2 & 4 & 6 \end{array}\right] \quad B=\left[\begin{array}{l} -2 \\ 3 \\ 12 \end{array}\right] Show that A*B is not the same as B*A.