18-35 Weighted-average method, spoilage. World Class Steaks is a meat-processing firm based in Texas. It operates under the weighted-average method of process costing and has two departments: preparation (prep) and shipping. For the prep department, conversion costs are added evenly during the process, and direct materials are added at the beginning of the process. Spoiled units are detected upon inspection at the end of the prep process and are disposed of at zero net disposal value. All completed work is transferred to the shipping department. Summary data for May follow: For the prep department, summarize the total costs to account for and assigo those costs to units completed and transferred out (including normal spoilage), to abnormal spoilage, and to units in ending work in process. (Problem 18-37 explores additional facets of this problem.)