On a scale drawing with a scale of 1/20, the height of the building is 8 inches. How tall is the actual building in feet?

That means its downgraded to 1/20 of actual height, let actual height is x. Then

(1/20) * x = 8, x = 20 * 8 = 160, actual height = 160 inch

160 inch = 160/12 feet = 13 1/3 feet or 13.333 feet.