As a marketing analyst, you would like to measure the impact of price and advertising on sales. You now have weekly sales data as Sales, price data as Price, and advertising data as Ad. Based on the data provided a. Fit a multiple regression model using Sales, Price and Ad, please write down the equation, and interpret how Sales is affected by Price and Ad. b. Some researchers claim that the impact of Price on Sales is influenced by the level of Advertising. Please propose and run a regression analysis to test the claim. Hint: there may be interaction between Price and Ad. . c. Based on model b, a researcher wants predict the expected Sales when Price is 9, and Ad is 8. What is the result you will provide?

C4 30.3 46.1 emerging C5 47.9 14.1 emerging C6 54.9 8.8 emerging C7 36.7 30 emerging C8 24.3 69.1 emerging C9 31.8 41.8 emerging C10 46.2 15.8 emerging C11 38.6 26.4 emerging C12 60.5 6 emerging C13 45.1 17 emerging C14 46.3 15.7 emerging C15 36.9 29.5 emerging C16 36.2 31 emerging C17 23.9 71.2 developed C18 20.3 90.9 developed C19 20.6 89.1 developed C20 22.3 79.2 developed C21 22.1 80.3 developed C22 20.2 91.6 developed C23 24.3 69.4 developed C24 28.6 51.8 developed C25 23.4 73.7 developed C26 22.2 79.9 developed C27 21.4 84.6 developed C28 23.3 74.1 developed C29 20.8 87.8 developed