#### Answer

$\sqrt[10]{m}$

#### Work Step by Step

Using $a^{m/n}=\sqrt[n]{a^m}=(\sqrt[n]{a})^m$, the given expression, $
\sqrt{\sqrt[5]{m}}
,$ is equivalent to
\begin{array}{l}\require{cancel}
\left( \sqrt[5]{m} \right)^{\frac{1}{2}}
\\\\=
\left( m^{\frac{1}{5}} \right)^{\frac{1}{2}}
\\\\=
m^{\frac{1}{5}\cdot\frac{1}{2}}
\\\\=
m^{\frac{1}{10}}
\\\\=
\sqrt[10]{m^1}
\\\\=
\sqrt[10]{m}
.\end{array}