Calculate the volume of a sphere where the radius is 9 meters

Scrub a dub toothbrushes are $4.00 each. there is a 10% discount, but there is also a 6% sales tax after the discount is applied. what is the new price after tax? round to the nearest penny

If x+y+z=0 what is the value of [tex] {x}^{3} + {y}^{3} + {z}^{3} [/tex]

Plzzz answer both questions and i will give you 100 points