What integer does 357 need to be divided by to equal -21

Abouncy ball is dropped such that the height of its first bounce is 5.5 feet and each successive bounce is 64% of the previous bounce's height. what would be the height of the 7th bounce of the ball? round to the nearest tenth (if necessary).

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

Find the greatest common factor of the followig monomials 21u^5v,3u^4v^6, and 3u^2v^5