January Beginning inventory Units produced Units sold Ending inventory 500 400 100 Excerpt from Wallis Corporation S Selling price Direct materials Direct labor Variable manufacturing overhead Variable selling and administrative expenses Pixed manufacturing overhead Fixed selling and administrative expenses Per Unit Per Month $ 100 30 20 10 7 $ 10,000 3,000 What is the company's contribution margin for January? O $200 $13,200 O $26,800 O $40,000