### Instruction: Express $\left(\frac{16}{625}\right)^{\frac14}$ a common fraction.### Response: To find the fourth root of a fraction, I can take the fourth root of the numerator and the denominator separately.
The fourth root of 16 is 2, because 2 to the fourth power is 16.
The fourth root of 625 is 5, because 5 to the fourth power is 625.