Walsh Corporation, which has only one product, has provided the following data concerning its most recent month of operations: 145 0 Selling price $ Units in beginning inventory Units produced Units sold Units in ending inventory 3,600 3,400 200 Variable costs per unit: Direct materials $ 35 Direct labor $ 57 Variable manufacturing overhead. $ 3 Variable selling and administrative expenses $ Fixed costs: Fixed manufacturing overhead $ 79,200 5 Fixed selling and administrative expense $ 64,600 The total contribution margin for the month under variable costing is: Select one: oa. $149,600 O b. $91,800 o c. $166,600 O d. $70,400