A company produces a single product. Variable production costs are $12 per unit and variable selling and administrative expenses are $3 per unit. Fixed manufacturing overhead totals $36,000 and fixed selling and administration expenses total $40,000. Assuming a beginning inventory of zero. production of 4,000 units and sales of 3, 600 units, the dollar value of the ending inventor* under variable costing would be: $4, 800 $ 8, 400 $6,000 $3,000