2.83 Alcohol and calories in beer. Figure 2.12 (page 98) gives a scatterplot of calories versus percent alcohol in 159 brands of domestic beer.

1. (a) Find the equation of the least-squares regression line for these data.

2. (b) Find the value of r² and interpret it in the regression context.

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   Table : TABLE 2.1 Four Data Sets for Exploring Correlation and Regression

   Data Set A
   x	10	8	13	9	11	14	6	4	12	7	5
   y	8.04	6.95	7.58	8.81	8.33	9.96	7.24	4.26	10.84	4.82	5.68
   Data Set B
   x	10	8	13	9	11	14	6	4	12	7	5
   y	9.14	8.14	8.74	8.77	9.26	8.10	6.13	3.10	9.13	7.26	4.74
   Data Set C
   x	10	8	13	9	11	14	6	4	12	7	5
   y	7.46	6.77	12.74	7.11	7.81	8.84	6.08	5.39	8.15	6.42	5.73
   Data Set D
   x	8	8	8	8	8	8	8	8	8	8	19
   y	6.58	5.76	7.71	8.84	8.47	7.04	5.25	5.56	7.91	6.89	12.50

3. (c) Write a short report on the relationship between calories and percent alcohol in beer. Include graphical and numerical summaries for each variable separately as well as graphical and numerical summaries for the relationship in your report.