What is pm ⋅ pn equal to?

Aflagpole broke in a storm. it was originally 8 1 81 feet tall. 2 8 28 feet are still sticking straight out of the ground, where it snapped, but the remaining piece has hinged over and touches the ground some distance away. how far away is the end of the pole from the base of the pole along the ground?

Prove that 16^4-2^13-4^5 is divisible by 11.

Find the solution on the interval [0, 2pi)