Chapter 11.5, Problem 49SE

For the following exercises, use the matrices below to perform the indicated operation if possible. if not possible, explain why the operation cannot be performed. (Hint: $A^2=A\cdot A$ )
$A=\left[\begin{array}{cc}1& 0\\ 2& 3\end{array}\right],B=\left[\begin{array}{l}\begin{array}{ccc}-2& 3& 4\end{array}\\ \begin{array}{ccc}-1& 1& -5\end{array}\end{array}\right],C=\left[\begin{array}{c}0.5\\ 1\\ -0.5\end{array}\begin{array}{c}0.1\\ 0.2\\ 0.3\end{array}\right],D=\left[\begin{array}{ccc}1& 0& -1\\ -6& 7& 5\\ 4& 2& 1\end{array}\right]$

49. $A\left(BC\right)$