Matrix Inc. calculates cost for an equivalent unit of production using the weighted-average method. Data for July: Work-in-process inventory, July 1 (36,000 units): Direct materials (100% completed) $ 122,400 Conversion (50% completed) 76,800 Balance in work in process inventory, July 1 $ 199,200 Units started during July 90,000 Units completed and transferred 102,000 Work-in-process inventory, Ju 31: Direct materials (100% completed) 24,000 Conversion (50% completed) Cost incurred during July: Direct materials $ 180,000 Conversion costs 288,000 Cost per equivalent unit for materials under the weighted-average method is calculated to be: $3.00. $2.00. O $3.10. $3.20. O $2.40