To evaluate \( 6^{-2} \), we can use the property of negative exponents:
\[ a^{-n} = \frac{1}{a^n} \]
So,
\[ 6^{-2} = \frac{1}{6^2} \]
Calculating \( 6^2 \):
\[ 6^2 = 36 \]
Thus,
\[ 6^{-2} = \frac{1}{36} \]
Now, let's look at your options:
- \( \frac{1}{2^6} \) is not equal to \( \frac{1}{36} \).
- \( 36 \) is not equal to \( \frac{1}{36} \).
- \( \frac{1}{2^6} \) is the same option as the first one.
- \( \frac{1}{36} \) is indeed equal to \( 6^{-2} \).
Therefore, the equivalent expression is:
4. one thirty-sixth.