GDP
The scatterplot shows the gross domestic product (GDP) of the United States in billions of dollars plotted against years since 1950.
![166_GRAPH.jpg](https://secure.tutorsglobe.com/CMSImages/166_GRAPH.jpg)
a) Does the value 97.2% suggest that this is a good model? Explain.
b) Here's a scatterplot of the residuals. Now do you think this is a good model for these data? Explain?
![138_graph 1.jpg](https://secure.tutorsglobe.com/CMSImages/138_graph 1.jpg)