The audience for a product's advertising can be divided into two segments according to the degree of exposur  received as a result of the advertising. These segments are groups of consumers who receive high (H) or low (L) exposure to the advertising. A company is interested in exploring whether its advertising effort affects its product's market share. Accordingly, the company

identifies 24 sample groups of consumers who have been exposed to its advertising, twelve groups at each exposure level. Then, the company determines its product's market share within each group

a. Write a regression model that expresses the company's market share as a function of advertising exposure level. Define all terms in your model, and list any assumptions you make about them

b. The data in the table below were obtained by the company. Fit the model you constructed in part a to the data

c. Is there evidence to suggest that the firm's expected market share differs for the two levels of advertising exposure? Test using a = .0