Suppose that $A, B, C, D$, and $E$ are matrices over $\mathbb{F}$ having the following sizes:
$A$ is $4 \times 5, B$ is $4 \times 5, C$ is $5 \times 2, D$ is $4 \times 2$,
Determine whether the following matrix expressions are defined, and, for those that are defined, determine the size of the resulting matrix.
(a) $B A$
(b) $A C+D$
(c) $A E+B$
(d) $A B+B$
(e) $E(A+B)$
$(f) E(A C)$