Correct. Simplify the expressions $\displaystyle{{\left({{x}}^{{-{{3}}}}{{y}}^{{5}}\right)}}^{{-{{2}}}}\usepackage{cmbright}\Huge\$ and $\displaystyle{{\left({{x}}^{{2}}{{y}}^{{-{{3}}}}\right)}}^{{-{{4}}}}\usepackage{cmbright}\Huge\$ first, then multiply them, and then cube that entire quantity. It simplifies to $\displaystyle{{x}}^{{-{{6}}}}{{y}}^{{6}}\usepackage{cmbright}\Huge\$ .