Question 1:
For this case we have the following expression:

We eliminate similar terms in the numerator and denominator:

By definition of division of powers of the same base we have to place the same base and subtract the exponents:

ANswer:
Option D
Question 2:
For this case we must indicate which expression is not equal to 125.
We tested option A:

Simplifying we have:

The expression is not equal to 125.
Answer:
option A