The following cost behavior pattern describes anticipated manufacturing overhead costs for 2019: $240,000 + $8/unit. During the year, 30,000 units were produced and 28,000 units were sold.

Required:

Calculate the manufacturing overhead unit cost for 2019 using variable costing and absorption costing, and then calculate the difference in operating income for 2019 using variable costing versus absorption costing. Explain the difference.