(a)[2]
$P=\begin{pmatrix}4&0\\-2&3\end{pmatrix}$ and $Q=\begin{pmatrix}1&2\\0&-1\end{pmatrix}$. Evaluate the product $PQ$.
(b(i))[1]
$M=\begin{pmatrix}3&-1\\2&k\end{pmatrix}$. The determinant of matrix $M$ is $-4$. Determine the value of $k$.
(b(ii))[1]
Determine $M^{-1}$.