Regression methods were used to analyze the data from a study investigating the relationship between roadway surface temperature (x) and pavement deflection (y). Summary quantities were n = 20, >yi = 12.7, Cry? = 8.8, Cixi = 1487 , 21 x, = 143, 215, Liliyi = 1083. (a) Calculate the least squares estimates of the slope and intercept. Graph the regression line. (12 points) (b) Use the equation of the fitted line to predict what pavement deflection would be observed when the surface temperature is 85 F. (4 points) (c) What is the mean pavement deflection when the surface temperature is 90 F? (4 points) (d) What change in mean pavement deflection would be expected for a 1 F change in surface temperature? (4 points)