Bethel, Inc. has collected the following data. (There are no beginning inventories.) Units produced 580 units Sales price $150 per unit Direct materials $18 per unit Direct labor $15 per unit Variable manufacturing overhead $5 per unit Fixed manufacturing overhead $18,000 per year Variable selling and administrative costs $5 per unit Fixed selling and administrative costs $11,500 per year What is the operating income using variable costing if 500 units are sold? Answer: $24,000 *****please show your work******