3erasers cost $4.41 which equations would determine the cost of 4 erasers

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).

If i have one apple and give you the apple, how many apples do i have?

Which function has the domain x> -11?