B. If you deposit your monthly fuel savings at the end of each month into an annuity that pays 5.2% compounded monthly, how much will have saved at the end of eight years? (Round to the nearest dollar as needed.)

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