The Plump Turkey Sales Company is a retail business that sells a single product. The company's revenues and expenses for the last 3 years are given below: Plump Turkey Sales Comparative Income Statement 2019 2020 2021 Sales in units 170,900 187,990 216,189 Sales revenue $5,810,600 $6,391,660 $7,350,426 Less cost of goods sold $2,905,300 $3,195,830 $3,675,213 Gross margin 2,905,300 3,195,830 3,675,213 Less operating expenses: Shipping expense 581,060 639,166 735,043 Advertising expense 70,000 70,000 70,000 Salaries and commissions 143,000 161,750 180,500 Insurance expense 9,000 9,000 9,000 Depreciation expense 42,000 42,000 42,000 Total operating expenses 845,060 921,916 1,036,543 Operating Income $2,060,240 $2,273,914 $2,638,670 Required: a. Based on cost behaviour experienced in prior 3 years above, identify which expenses are variable, which expenses are fixed and which expenses are mixed (use the chart below). (4.5 marks) Expense Description Type Cost of goods sold Variable Shipping expense Variable Advertising expense Fixed Salaries and commissions Mixed Insurance expense Fixed Depreciation expense Fixed b. For those expenses listed above that you identified as mixed, separate each mixed expense into its variable and fixed components using the high-low method and state the cost formula for each mixed expense. (3 marks) Salaries & Commissions 9,599.34 c. Assume that for 2022 sales are projected to be 432,000 units Create a contribution margin income statement for 2022 assuming cost behaviour identified in a. and b. will not change. (3.5 marks)