Columbia Inc. has provided the following for three months of income statements: Sales in Units January 3,000 February 3,500 March 4,000 Sales 900,000 1,050,000 1,200,000 Less: cost of goods 540,000 630,000 720,000 sold Gross margin 360,000 420,000 480,000 Operating expenses: Advertising 25,000 25,000 25,000 Salaries & 175,000 197,500 220,000 Commissions Depreciation expense 25,000 25,000 25,000 Utilities expense 75,000 87,000 99,000 Total operating 300,000 334,500 369,000 expenses Net Income 60,000 85,500 111,000 Required: For each of the mixed costs, separate them out into their variable and fixed components using the high-low method. State the cost equation for each mixed cost. HINT: There are 2 mixed costs