Hamada Inc, manufactures cover for car seats. It's costing system utilizes two cost categories, direct materials and conversion costs. Each product must pass through two Departments X and Y. Direct materials are added at the beginning of production. Conversion costs are allocated evenly throughout production Data for Department X for February 2020 are: WIP beginning, 40% complete 300 units. Units started during February 600 units, and WIP ending 30% complete 100 units. The equivalent units of direct materials using weighted average method is: O a. 500 units. b. 900 units c. 400 units d. 800 units