If the fixed manufacturing costs were $12,285 and the fixed selling and administrative expenses were $4,980, prepare an income statement according to the variable costing concept. Round all final answers to whole dollars. Joplin Company Variable Costing Income Statement For the Month Ended April 30 Sales Variable cost of goods sold: Variable cost of goods manufactured $ Inventory, April 30 Total variable cost of goods sold Manufacturing margin Variable selling and administrative expenses Contribution margin Fixed costs: Fixed manufacturing costs Fixed selling and administrative expenses Total fixed costs Operating income