(12 points) The product manager for a brand of all-natural herbal shampoo has compiled 15 weeks of data on the weekly sales of the brand (in units), the level of media advertising (in thousands of dollars), the price (in dollars), and the use of displays (in number of stores with the brand on an end-aisle display). She then carried out a multiple regression analysis on these data in order to calculate a price elasticity. Her data and the results of the regression analysis can be seen below. (a) Name each of the variables that were used in this multiple regression analysis. For each of these variables, indicate whether it was an independent variable or a dependent variable in this regression analysis. (b) Use these data and the results of the regression analysis to calculate the price elasticity for this shampoo brand. Show your work. (c ) Based on the course material, describe at least two issues that should lead the product manager to not entirely trust the price elasticity calculated from this analysis.

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