The Molding Department of Boswell Company has the following production data: beginning work process 30,000 units (60% complete), started into production 510,000 units, completed and transferred out 480,000 units, and ending work in process 60,000 units (40% complete). Assuming materials are entered at the beginning of the process, equivalent units for materials are: a. 540,000. b. 450,000. c. 480,000. d. 570,000