(5) Given that set $A$ has $m\left(m \in \mathbf{N}^{*}\right)$ elements, if one element is added to $A$, the number of its subsets will increase by $\qquad$; if $k\left(k \in \mathbf{N}^{*}, k \geqslant 2\right)$ elements are added to $A$, the number of its subsets will increase by $\qquad$.
(5) $2^{m} ;\left(2^{k}-1\right) \cdot 2^{m}$