How is variable selling and administrative expenses calculated?

Variable Costing Income Statement For the Month Ended March 31 Line Item Description Amount Amount Sales 6,250,000 Variable cost of goods sold 2,750,000 Manufacturing margin 3,500,000 Variable selling and administrative expenses 125,000 Contribution margin 3,375,000 Fixed costs: Fixed factory overhead costs 600,000 Fixed selling and administrative expenses 45,000 Total fixed costs V 645,000 Operating income V 2,730,000