Answer:
The last expression is correct
Step-by-step explanation:
We have been given the following expression for simplification;
The bases of the two expressions are the same. They are both equal to 4. When multiplying numbers with the same base, we simply add their exponents. In this case our exponents are;
4 and -9
adding them we have;
4 + (-9) = -5
The simplified expression thus becomes;