A surveyor needs to measure the width of a building. He identifies two points and at ground level on opposite sides of the building. He then walks to a point a distance away from the building: point . He measures the distance from to as feet, the distance from to as feet, and the measure of as . How wide is the building? Round your answer to the nearest foot, then determine whether it is reasonable given the context of the problem.

Draw and label a sketch of the situation.

Find using the Law of Cosines.

Determine if the answer is reasonable.

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