Aaker Corporation, which has only one product, has provided the following data concerning its most recent month of operations:

Selling price	$99
Units in beginning inventory	0
Units produced	6,300
Units sold	6,000
Units in ending inventory	300
Variable costs per unit:
Direct materials	$12
Direct labor	$42
Variable manufacturing overhead	$6
Variable selling and administrative	$6
Fixed costs:
Fixed manufacturing overhead	$170,100
Fixed selling and administrative	$24,000

What is the net operating income for the month under variable costing?

$8,100

($14,100)

$12,000

$3,900