Sam's Swimming Pool Cleaning has a annual net income of $46,900. Sam charges $25 per week for each of his customers for 52 weeks. His annual operating expenses, including labor and supplies, are $48,000. How many customers does Sam's Swimming Pool Cleaning have? a. 21
b. 38
c. 44
d. 73

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