The Nambe Mills company has a line of metal tableware products that require a polishing step in the manufacturing process. To help plan the production schedule, the polishing times for 59 products were recorded, along with the product type and the relative sizes of these products, measured in terms of their diameters.

This information can be found in polishing.sav. Use linear regression to determine whether the polishing time can be predicted by product size.

Before running the regression, you should examine a scatterplot of polishing time by product size to determine whether a linear model is reasonable for these variables.