A sales manager is interested in evaluating the effectiveness of product literature. There are five different types of brochures currently in use. He asks four salespeople in each of the four regions of the country to evaluate the effectiveness of each of the brochures. The results of a two-way ANOVA are presented below. Source of Variation Sum of Squares Region of country 36.40 Brochure type 13.40 Interaction 31.32 Error 125.2 a. A two-way analysis of variance table is displayed below with missing values, denoted by asterisks (*). Fill in the missing values Source of Variation SS df MS F-ratio Region of country 36.40 Brochure type 13.40 Interaction 31.32 Error 125.2 2.087 Total 206.32 79 b. Is there sufficient evidence to reject the null hypothesis that there is no difference between the regions of the country? Use a = 0.05. c. Is there sufficient evidence to reject the null hypothesis that there is no difference between different types of brochures? Use a = 0.05. d. Is there sufficient evidence to reject the null hypothesis that there is no interaction between region of the country and brochure type? Use a = 0.05