Answer:
It's C because (m^8)^1/4 can simplify to (m^2)
and (n^-4)^1/4 can simplify to (n^-1), which would then become 1/n because it is a negative exponent.
Combine the two and you get: m^2/n
Step-by-step explanation:
x + y = 50
x = 3y - 6
3y - 6 + y = 50
4y = 56
y = 14
. Filling in accordingly, 
. This simplifies to 
and 36=6x. Therefore, x = 6 so the bases are 6 and 12.