Which equations are correct? Select each correct answer.
5x4 (4x2) = 2026
62% (62") = 36a25
3z? (422) = 122
664 (-364) = -1868

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