Question: Over the past year, the Wisconsin Regional Sewage District (WRSD) has received considerable negative attention over incidents in which the untreated sewage has been released into Lake Michigan. The director of WRSD argues that heavy rain, rather than actions taken by the district, is to blame for the sewage release incidents. To prove her point, the director regresses the number of gallons of untreated sewage released into the lake per month (SEWAGE) on the total rainfall per month (RAIN) in inches.

Use the regression results below to tell the director:

a. Is there a significant relationship between the amount of rainfall and the amount of sewage released?

b. Is the direction of the relationship consistent with the director’s argument?

c. What percent of the variation in the amount of untreated sewage released is explained by rain fall? Is the relationship between sewage and rainfall weak, moderate, or strong?