Haley simplifies 3^5 · 4^5 and gets the result 12^10, but lacey is not sure. is haley correct?

Aplane flies around trip to philadelphia it flies to philadelphia at 220 miles per hour and back home with a tailwind at 280 miles per hour if the total trip takes 6.5 hours how many miles does the plane fly round trip

Precalculus question, image attached.

In a column proof the right column states your reasons