4. Regression model for 15 cars to predict mpg is as follows: mpg = 23 - 0.084 * HP i ) Predict mpg at HP 220. If the actual mpg is 31 find the residual. ii ) What is the value of slope? Explain the meaning of slope in this context and the nature of the association. iii) Graph the Regression line by showing two points on the line with proper labels. Show the residual on your model. Let us assume HP range : 85 - 270 and mpg range : 23 to 45