Simplify a5 ÷ a4, a ≠ 0.
a) 5a
b) a
c) 4a
d) 1

I assume you mean a^5 divided by a^4. This is a rule that applies to all exponents in that when you divide exponents, you subtract the top from the bottom. So, 5-4 is 1 and that would the answer is b

D.