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A boat sails directly toward a 250-m skyscraper that stands on the edge of a harbor. The angular size of the building is the angle formed by lines from the top and bottom of the building to the observer (see figure). Complete parts a and b below. 250 m a. Use a trigonometric equation to find an expression for the angle, 0, in terms of x. 0 = tan - 1 250 X (Type an equation.) Op What is the rate of change of the angular size, -, when the boat is x = 500 m from the building? rad/m Round to five decimal places as needed.)