9-1: Achilles Auto makes and sells batteries. In 2017, it made 100,000 batteries and sold 75,000 of them, at a average selling price of $60 per unit. The following additional information relates to Achilles Auto for 2017: Direct materials $ 20.00 per unit Direct manufacturing labor $ 4.00 per unit Variable manufacturing costs $ 1.00 per unit Sales commissions $ 6.00 per part Fixed manufacturing costs $750,000 per year Administrative expenses, all fixed $270,000 per year What is Achilles Auto's inventoriable cost per unit using (a) variable costing, and (b) absorption costing