Green Company sells its product for $11,000 per unit. Variable costs per unit are: manufacturing, $6,000; and selling and administrative, $125. Fixed costs are: $30,000 manufacturing overhead, and $40,000 selling and administrative. There was no beginning 2020,16 units in 2021 , and 24 units in 2022. Income under variable costing for 2021 is a. $8,000. b. $22,000. c. $16,000, d. $14,000