Lubricants, Inc., produces a special kind of grease that is widely used by race car drivers. The grease is produced in two processing departments—Refining and Blending. Raw materials are introduced at various points in the Refining Department. The following incomplete Work in Process account is available for the Refining Department for March: Work in Process—Refining Department March 1 balance 31,300 Completed and transferred to Blending ? Materials 157,600 Direct labor 80,200 Overhead 476,000 March 31 balance ? The March 1 work in process inventory in the Refining Department consists of the following elements: materials, $7,900; direct labor, $3,300; and overhead, $20,100.