list the expressions from greatest to least.

5^(-10) / 5^(-12)
2^(-2) c 2^(-3)
4^2 x 4^(-1)
7^8/7^8

From greatest to least:

1. 4^2 x 4^(-1)
2. 5^(-10) / 5^(-12)
3. 2^(-2) x 2^(-3)
4. 7^8 / 7^8