A bookmark has a perimeter of 20 centimeters and an area of 21 square centimeters. What are the dimensions of the bookmark?

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The solution set for 5v2 – 125 = 0 is

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