There are two ways to do this, but I'm only gonna use the first way.
First, to move the 2^-8 to the numerator and combine the exponents, and keep the same base and you get 2^ 14. Next, to divide powers, you subtract the exponents and keep the base. So 2^14/2^10 gives you 2^4. If you want to simplify it further, you'll get 16.