calculate the degree of operating leverage given the following information: sales of $25,000; variable costs $13,000, and operating income of $7,000 for year one, and sales of $40,000; variable costs of $15,000; and operating income of $16,000 for year 2. Your answer should be expressed as a percentage, and rounded to two decimal places. (FOr this problem, specifically calculate the difference between the sales and the operating income for each of the given years. This will allow you to calculate the degree of operating leverage.)