MrBillDoesMath!
Answer: The first radio button choice 8/3 * m^8
Steps:
120 (m^ 16) / 45 (m^8) =
120/45 * (m^16)/(m^8) =
Simplify 120/45 (15 or 5 *3 divides each). Since base "m" is same in both terms simply subtract exponents.
8/3 ( m^(16 - 8)) =
8/3 * m^8
MrB