Variable production costs Plastic for casing $ 171,500 Wages of assembly workers 490,000 Drum stands 215,600 Variable selling costs Sales commissions 161,700 Fixed manufacturing costs Taxes on factory 6,000 Factory maintenance 12,000 Factory machinery depreciation 72,000 Fixed selling and administrative costs Lease of equipment for sales staff 12,000 Accounting staff salaries 62,000 Administrative management salaries 142,000 Required: 1. Prepare a contribution margin income statement for the year. 2. Compute its contribution margin per unit and its contribution margin ratio. 3. For each dollar of sales, how much is left to cover fixed costs and contribute to operating income