This answer is equal to $\displaystyle{{5}}^{{1}}\usepackage{cmbright}\Huge\$ . Since $\displaystyle{{n}}^{{-{x}}}=\frac{{1}}{{{n}}^{{x}}}\usepackage{cmbright}\Huge\$ , this tells you that $\displaystyle{{5}}^{{-{{1}}}}=\frac{{1}}{{{5}}^{{1}}}\usepackage{cmbright}\Huge\$