If two matrices $A$ and $B$ are of order $p \times q$ and $r \times s$ respectively,they can be subtracted only if:

$A$ matrix whose elements $a_{ij}$ are defined by $a_{ij} = \frac{1}{3}|i - 5j|$,where $i, j = 1, 2, 3$,is:

The number of symmetric matrices of order $3 \times 3$,with all the entries from the set $\{0, 1, 2, 3, 4, 5, 6, 7, 8, 9\}$,is:

If $A = \begin{bmatrix} 1 & a \\ 0 & 1 \end{bmatrix}$,then $A^n$ (where $n \in N$) equals

$\cos \theta \begin{bmatrix} \cos \theta & \sin \theta \\ - \sin \theta & \cos \theta \end{bmatrix} + \sin \theta \begin{bmatrix} \sin \theta & - \cos \theta \\ \cos \theta & \sin \theta \end{bmatrix} = $

Let $A=\left[\begin{array}{ccc}1 & -1 & 2 \\ 0 & 3 & 4\end{array}\right]$,$B=\left[\begin{array}{ccc}4 & 0 & -3 \\ -1 & -2 & -3\end{array}\right]$ and $C=\left[\begin{array}{cccc}2 & -3 & 0 & 1 \\ 5 & -1 & -4 & 2 \\ -1 & 0 & 0 & 3\end{array}\right]$,what is $A^T B$ ?