Wessner Corporation has provided the following information: Cost per Period Cost per Unit $6.20 $ 2.80 $1.45 Direct materials Direct labor Variable manufacturing overhead Fixed manufacturing overhead Sales commissions Variable administrative expense Fixed selling and administrative expense $12,000 $1.00 $ 0.55 $ 4,000 If the selling price is $25.00 per unit, the contribution margin per unit sold is closest to: Multiple Choice o $16.00 o $9.00 o $11.55 o $13.00