On rural highways, the average speed S (in miles per hour) is related to the amount of curvature C (in degrees) of the road. On a straight road (C = 0), the average speed is 46.26 miles per hour. This decreases by 0.746 mile per hour for each additional degree of curvature. a) The slope of the linear function between S and C is mile per hour per degree. (Give your answer to three decimal places.)