On April 30, the end of the first month of operations, Joplin Company prepared the following income statement, based on the absorption costing concept: Joplin Company Absorption Costing Income Statement For the Month Ended April 30 Sales (6,400 units) $134,400 Cost of goods sold: Cost of goods manufactured (7,400 units) $111,000 Inventory, April 30 (1,000 units) (15,000) Total cost of goods sold Gross profit Selling and administrative expenses Operating income (96,000) $38,400 (23,950) $14,450