Develop a model to predict the total sales volume on the market. You may use some results from Part 1. a. Calculate the total sales forecast in a new worksheet Sales Model in the data le hw- data.xlsb. b. In worksheet Sales, ll the cells marked green with your total sales forecast (calculated in part a). Your results will be evaluated based on the MAPE of the total sales forecast for the holdout sample. For the week ending in day 1112, calculate the prices of the Gold Rush brand (4 products) to maximize Gold Rush's total profits while keeping other inputs (Promo, Bottle, SizePromo and competitor prices) fixed. The unit costs are $1.30 for "VITAMIN\" and "SPECIAL\