The data in the table represent the weights of various domestic cars and miles per gallon in the city for the 2008 model year. For these data, the least-squares regression line is y=-0.006x+41.946.

A twelfth car weighs 3,425 pounds and gets 13 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 R^2?

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

\f