11. The Bayview Convenience Store sells a range of different products, such as milk, canned goods, hardware, and magazines. On average, the store the goods it buys by 50%; thus, something that cost $1 would be sold for $1.50, and the gross margin would be one-third of the selling price. Fixed costs are $5,000 per month. marks up Required Calculate the following: (a) The contribution margin ratio (b) The monthly break-even sales revenue (c) The sales revenue needed to make an operating profit of $2,000 per month S