4. The Toyota Camry is one of the best-selling cars in North America. The cost of a previously owned Camry depends on many factors, including the model year, mileage, and condition. To investigate the relationship between the cars mileage and the sales price for Camrys, the dataset Camry shows the mileage and sale price for 19 sales. (20 points).

a. Develop a scatter chart for these data with miles as the independent variable. What does the scatter chart indicate about the relationship between price and miles? (5 points).

b. Develop an estimated regression equation showing how price is related to miles. What is the estimated regression model? (5 points).

c. Test whether each of the regression parameters 0 and 1 is different from zero at a 0.01 level of significance. Interpret the estimated regression parameters. (5 points).

d. How much of the variation in the sample values of price does the model estimated in

part (b) explain? (5 points)

\begin{tabular}{|r|r|} \hline \begin{tabular}{c} Miles \\ (1000) \end{tabular} & \begin{tabular}{c} Price \\ ($1000s) \end{tabular} \\ \hline 22 & 16.2 \\ \hline 29 & 16.0 \\ \hline 36 & 13.8 \\ \hline 47 & 11.5 \\ \hline 63 & 12.5 \\ \hline 77 & 12.9 \\ \hline 73 & 11.2 \\ \hline 87 & 13.0 \\ \hline 92 & 11.8 \\ \hline 101 & 10.8 \\ \hline 110 & 8.3 \\ \hline 28 & 12.5 \\ \hline 59 & 11.1 \\ \hline 68 & 15.0 \\ \hline 68 & 12.2 \\ \hline 91 & 13.0 \\ \hline 42 & 15.6 \\ \hline 65 & 12.7 \\ \hline 110 & 8.3 \\ \hline \end{tabular}