Aaron Corporation, which has only one product, has provided the following data concerning its most recent month of operations: Selling price $ 90 Units in beginning inventory Units produced Units sold Units in ending inventory 3,400 3,000 400 Variable costs per unit: Direct materials Direct labor Variable manufacturing overhead Variable selling and administrative expense Fixed costs: Fixed manufacturing overhead Fixed selling and administrative expense HAH $ $ 54,400 3,000 What is the net operating income for the month under variable costing? $6,400 $5,600 $(20,400) $12,000