Write the expanded form of the following.

$z^5$

If the given expansion in exponential form is equal to $a^k$, then find the value of $k$.

$a\times a\times a\times ..............l$ times.

If the given expansion in exponential form is equal to $5^k$, then find the value of $k$.

$5\times 5\times 5\times 5\times ..............n$ times.

If the given expansion in exponential form is equal to $q^k$, then find the value of $k$.

 $q\times q\times q\times ..............15$ times.

Write the given expansion in exponential form.

$r\times r\times r\times ..............b$ times is $r^k$. Then find the value of k.