Columbia Corporation produces a single product. The company's variable costing income statement for November appears below tion Income Statement Sales ($19 per unit) Variable expenses $811,380 Variable cost of goods sold Variable selling expense Total variable expenses Contribution margin Fixed expenses: 512,480 85,480 597,880 213, 586 Manufacturing Selling and administrative 143,640 5,918 179,558 5 33,950 Total fixed expenses Net operating income During November, 35.910 units were manufactured and 8.210 unts were in beginning inventory Vable pooncots havet on a pef unit basis over the past several months. he vace df to omnys mveoa n oeine 30 unade bsorphon cong o