Answer:
81x^4/y^8
Explanation:
1) You distribute the power of 4 to everything on the top and bottom of the fraction by multiplying all their exponents by 4.
2) You give 3^4, and now you have 81
3) You just give x a 4 as an exponent.
4) You give y an exponent of 8 since 2*4=8.
5) Your answer is 81x^4/y^8