If a firm spends more on advertising, is it likely to increase sales? Data on annual sales (in $100,000s) and advertising expenditures (in $10,000s) were collected for 20 firms in order to estimate the model Sales = β0 + β1 Advertising + . A portion of the Excel results is as follows:
a. Is the sign on the slope as expected? Explain. b. What is the sample regression equation? c. Predict the sales for a firm that spends $500,000 annually onadvertising.