Here's the expression that I'm having trouble with (sorry for the lack of ease of readability):

((2^-1)(x^-2)(y^-1))^-2((2x^-4)(y^3))^-2((16x^-3)(y^3))^0 / ((2x^-3)(y^-5))^2

The answers is:

x^18y^6 / 4

I've worked this problem over and over as many different ways as I could, but I've never got the correct answer. I would appreciate very much it if someone could post the steps to solving this problem.

Thanks for your time!