A business operated at 100% of capacity during its first month, with the following results: Sales (96 units) $480,000 Production costs (120 units): Direct materials $60,000 Direct labor 15,000 Variable factory overhead 21 27,000 Fixed factory overhead 24,000 126,000 Operating expenses: Variable operating expenses $6,040 Fixed operating expenses 3,180 9,220 The amount of contribution margin that would be reported on the variable costing income statement is Oa. $392,360 Ob. $389,180 Oc. $470,780 Od. $479,880