To simplify \( 6^{-2} \), we can use the property of exponents that states \( a^{-n} = \frac{1}{a^n} \).
Thus,
\[ 6^{-2} = \frac{1}{6^2} = \frac{1}{36} \]
So the equivalent expression for \( 6^{-2} \) is:
\[ \frac{1}{36} \]
The correct response is \( \frac{1}{36} \).