Which of these are correct?

5^ 8/5^6 = 25
6^7/ 6^-5 = 36
4^0/ 4^3 = 0
3^ 6/3 ^4 = 1/9

The correct statements are:

5^8/5^6 = 25 (This is correct because when you divide two numbers with the same base, you subtract the exponents, so 5^8/5^6 = 5^(8-6) = 5^2 = 25)

6^7/6^-5 = 36 (This is correct because when you divide two numbers with the same base, you subtract the exponents, so 6^7/6^-5 = 6^(7-(-5)) = 6^12 = 36)

3^6/3^4 = 1/9 (This is correct because when you divide two numbers with the same base, you subtract the exponents, so 3^6/3^4 = 3^(6-4) = 3^2 = 9)