magpie corporation uses the total cost concept of product pricing. below is the cost information for the production and sale of 57,800 units of its sole product. magpie desires a profit equal to a 23% rate of return on invested assets of $646,000. fixed factory overhead cost $38,300 fixed selling and administrative costs 7,400 variable direct materials cost per unit 5.02 variable direct labor cost per unit 1.88 variable factory overhead cost per unit 1.13 variable selling and administrative cost per unit 4.50 the cost per unit for the production and sale of the company's product is a.$12.53 b.$13.32 c.$0.79 d.$1.92