P4-21 Weightecd-Average Method; Analysis of Work in Procass F-Account Weston Products manufactures an industrial cleaning compound that goes through three processing departments-Grinding, Mixing, and Cooking. All raw materials are introduced at the start of work in the Grinding Department, with conversion costs being incurred evenly throughout the grinding process. The Work in Process T-account for the Grinding Department for a recent month is given below: Work in Process-Grinding Department Inventory, May 1 (18,000 Completed and transferred lbs., 1/3 processed) 21,800 to mixng May costs added: Raw materials (167,000 133.400 226.800 OS. Labor and overhead Inventory, May 31 (15,000 lbs., 2/3 processed) The May 1 work in process inventory consists of $14,600 in materials cost and $7,200 in labor and overhead cost. The company uses the weighted-average method to account for units and costs 1. 2. Prepare a production report for the Grinding Department for the month. What criticism can be made of the unit costs that you have computed on your production report