The Central \\.I"alle',.r Company.r is a manufacturing firm that produces and sells a single product. The company's revenues and expenses for the last four months are given below. Central Valley Company Comparative Monthly Income statements March April May June Sales in units 5,100 4,600 5,350 6,200 Sales revenue $703,800 $634,000 $?38,300 $855,600 Less: Cost of goods sold 360,700 342,200 376,950 427,000 Gross margin 335,100 292,600 361,350 420,600 Less: Operating expenses Shipping expense 62,100 57,100 65,350 71,500 Advertising expense 71,000 71,000 71,000 71,000 salaries a commissions 164,800 149,500 164,750 181,500 Insurance expense 9,100 9,100 9,100 9,100 Depreciation expense 40,000 40,000 40,000 40,000 Total operating expenses 347,000 326,700 350,200 373,100 Net income \"11,900: $l34,100) 5 11,150 $ 55,500 Required: 1. Management is concerned about the losses experienced during the spring and would like to know more about the cost behaviour. Develop a cost equation for each of the costs, COGS Shipping Y Salaries and commissions Y 2. Using the cost equations, prepare a contribution margin income statement (in good form) for September when 5,700 units are expected to be sold. CENTRAL VALLEY COMPANY Contribution Income Statement For the month ended September 30 Variable costs: Less fixed costs