Questions 8, 9, and 10 refer to the following situation: The FDA wishes to investigate if the tar contents (milligrams) vary among four brands of cigarettes. Three packs of each brand were selected, and one cigarette from each pack was placed in a smoking machine to determine the tar content. An Analysis of Variance was performed and here are the results (some parts are hidden): Analysis of Variance Table Response: tar DF Sum Sq Mean Sq F Value Pr ( > F) brand 3 116 0.0028 residuals 80 The value of the F-statistic for testing the equality of the means is: O 0.0028 O 13.05 O 4.35 11.60