Torri had 20$ to buy a birthday present for her dad. she decided to buy a dvd for $18. the sales tax is 7%. does she have enough money? (show work)

Gravel is being dumped from a conveyor belt at a rate of 25 ft3/min, and its coarseness is such that it forms a pile in the shape of a cone whose base diameter and height are always equal. how fast is the height of the pile increasing when the pile is 14 ft high? (round your answer to two decimal places.) ft/min