The data in the table represent the weights of various domestic cars and their miles per gallon in the city for the 2008 model year. For these data, the least-squares regression line is

y=0.006x+41.286.

A twelfth car weighs

3,425

pounds and gets

11

miles per gallon.(a) Compute the coefficient of determination of the expanded data set. What effect does the addition of the twelfth car to the data set have on

R2?

(b) Is the point corresponding to the twelfth car influential? Is it an outlier?