Some nuclear power plants utilize natural draft cooling towe

Some nuclear power plants utilize \"natural draft\" cooling towers in the shape of a hyperbot of solid obtained by rotating a hyperbola about its conjugate axis. Suppose that such a cooling tower has a base diameter of 400 feet and the diameter at its narrower point, 360 above the ground, is 200 feet. If the diameter at the top of the tower is 300 feet, how tall Vs the tower?

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