Answer:
A = 2.
Explanation:
When raising power to power and there is a base with a exponent and a coefficant, you need to know that the a exponent only belongs to the y. The 2 has a invisible 1 exponent. The new expression is now (2^1 y^a)^4 = 16y^8. Now it is time to solve it. 1x4 = 4 so it is (2^4 y^a) = 16y^8. 2^4 is also 2x2x2x2 which equals 16. Now for the a exponent, 8/4 = ?. 2. The new expression is 16y^2 and a = 2.