If five notebooks cost 5.25 how much would three notebooks cost

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).

Acircle has a circumference of 28.36 units what is the diameter of the circle

Witch represents the inverse of the function f(x)=1/4x-12