The cube root of 81 can be expressed mathematically as \( 81^{1/3} \). It's not a perfect cube, but we can approximate it.
Calculating it explicitly using a calculator or estimation, we find:
\[ \sqrt[3]{81} \approx 4.326 \]
From the options you provided:
- \( 81^{1/3} \)
- \(-9\)
- \(27\)
- \(9\)
None of these options correctly represent the cube root of 81. The closest approximation is approximately 4.326, but it appears there may have been a misunderstanding in the response options you provided.