4. Net Income by Store by Month (5 points) Hint: Find the margin of each sale by taking the selling price less the cost. Aggregate the total margin for each store by month. The margin less the S&A expenses is your income. 5. A Histogram of Profit Margins for each Product Class (5 points) Hint: Filter your products by class. Identify the maximum and minimum margin percentage. Think back to managerial accounting on how to get a profit margin . Create a histogram and create bins. Each bin should be 5% or .05