The Greenback Store's cost structure is dominated by variable costs with a contribution margin ratio of 0.45 and fixed costs of $115,900. Every dollar of sales contributes 45 cents toward fixed costs and profit. The cost structure of a competitor, One-Mart, is dominated by fixed costs with a higher contribution margin ratio of 0.80 and fixed costs of $329,400. Every dollar of sales contributes 80 cents toward fixed costs and profit. Both companies have sales of $610,000 for the month. Required: a. Compare the two companies' cost structures. b. Suppose that both companies experience a 20 percent increase in sales volume. By how much would each company's profits increase? GREENBACK STORE ONE-MART Amount $610,000 Percentage Amount Percentage Sales Variable cost Contribution margir Fixed costs Operating profit Greenback Store's profits increase by One-Mart's profits increase by