Correct. Apply the exponent to each factor in parentheses: $\displaystyle{{\left(-{4}\right)}}^{{2}}{{\left({x}\right)}}^{{2}}{{\left({{y}}^{{4}}\right)}}^{{2}}\usepackage{cmbright}\Huge\$

Simplify using the power rule: $\displaystyle{16}{{x}}^{{2}}{{y}}^{{{4}\cdot{2}}}={16}{{x}}^{{2}}{{y}}^{{8}}\usepackage{cmbright}\Huge\$