The Willis Tower (formerly the Sears Tower) in Chicago is 1454 ft tall. Assuming that it is a tall rectangle with a square base of 120 ft sides, calculate the maximum drag force on the building and the force when the wind is along the diagonal of the structure as a function of wind speed from Beaufort Wind Scales of strong breeze (28 mph) to hurricane (75 mph). Assuming that the wind field is uniform, calculate the moment about the base of the Tower also.
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