Apply the exponent 4 to each factor within the parentheses: $\displaystyle{{\left(-{2}\right)}}^{{4}}{{\left({{g}}^{{5}}\right)}}^{{4}}{{\left({{h}}^{{2}}\right)}}^{{4}}{\)}\usepackage{cmbright}\Huge\$

Simplify, using the Power Rule: $\displaystyle{16}{{g}}^{{{5}\cdot{4}}}{{h}}^{{{2}\cdot{4}}}={16}{{g}}^{{20}}{{h}}^{{8}}\usepackage{cmbright}\Huge\$