Help with simplifying these equations

I just need some help with these math problems, they are simple, but I am getting lost and not sure if I am doing them right.

The first problem is "Simplify ((z+2)^-3)((z+2)^-1)"

The second problem is "Simplify ((4/y)^3)((3/y)^4)"

I finished the rest of the assignment, but I keep getting weird answers on these two!

They're expressions, not equations.
(z + 2)^-3 ((z + 2)^-1) =
(z + 2)^(-3 + -1) =
(z + 2)^-4

((4/y)^3)((3/y)^4) =
(4^3/y^3)(3^4/y^4) =
(64 * 81)/(y^(3 + 4)) =
5184/y^7

i) (z+2)^-4

ii) 4^3*3^4/y^7