Which expressions have a value of 16 over 81 ? Choose two correct answers.

Squaring a fraction means squaring both its numerator and denominator: (4/9)² = 16/81, so choice C works. Raising a power to a power means multiplying the exponents: (2/3)⁴ = 2⁴/3⁴ = 16/81, so choice E works too.

AI-written and checked against the verified answer.