​Barrett, Inc. reports the following information for the year ended December​ 31: Beginning Finished Goods Inventory 70 units Units produced 450 units Units sold 520 units Sales price $ 150 per unit Direct materials $ 25 per unit Direct labor $ 10 per unit Variable manufacturing overhead $ 15 per unit Fixed manufacturing overhead $ 15 comma 600 per year Variable selling and administrative costs $ 6 per unit Fixed selling and administrative costs $ 13 comma 000 per year The beginning Finished Goods Inventory costs were $ 3 comma 600 under absorption costing and $ 3 comma 500 under variable costing. What is the operating income using variable​ costing