Answer:
b^19
Step-by-step explanation:
In the first factor, we need to use a formula to simplify. The formula is x^a^b = x^(ab). So that means that our first factor simplifies to b^15. Then we add up the powers to simplify it even more. b^15 * b^4 = b^19 using another formula. Therefore b^19 is the answer.
