Jointsoft is a great overthecounter arthritis medication, but who will ever know about it? Unfortunately, many people with arthritis tend to be elderly and rather immobile, so advertisers of arthritis medications face limitations in ways to get their messages across. Currently, their best modes of advertisement are commercials on daytime TV, advertisements in select magazines, fliers in convalescent homes, and advertisements on certain Web pages. Marketing managers for Jointsoft are investigating these four modes of advertisement in four small communities (with a different mode of advertisement in each community). The marketing managers have selected 47 days at random and are looking at the daily sales (in dollars) in each of the communities on each of these days. Here is what they have to work with. Sample Sample Sample Groups size mean variance TV 47 594.2 2569.3 Magazines 47 581.7 1947.2 Fliers 47 580.1 2177.7 Web pages 47 569.4 3226.5 i Send data to calculator V i i Send data to Excel i Suppose that the marketing managers perform a oneway, independentsamples ANOVA test to decide if there are differences in the mean daily sales arising from the four modes of advertisement. (So, they're assuming that the only difference among the four communities is the mode of advertisement used in it.) Such a test uses the following statistic. Variation between the samples Variation within the samples For the information in the chart above, F t 1.96. (a) Give the numerator degrees of freedom of this F [I statistic. (b) Give the denominator degrees of freedom of this F [I statistic. (c) Using the 0.01 level of significance, can the marketing managers conclude that the mean daily Y N sales arising from at least one of the modes of 0 es 0 0 advertisement differs from the others