Because most of the parts for its irrigation systems are standard, Waterways handles the majority of its manufacturing as a proce cost system. There are multiple process departments. Three of these departments are the Molding. Cutting, and Welding departments. All items eventually end up in the Packaging Department, which prepares items for sale in kits or individually. The following information is available for the Molding department for January. Work in process beginning: Units in process 21,600 Stage of completion for materials 80% Stage of completion for labor and overhead 30% Costs in work in process inventory: Materials $167,780 Labor 67.630 Overhead 17,310 Total costs in beginning work in process $252.720 Units started into production in January 59.900 Units completed and transferred in January 58,400 Costs added to production: Materials $278,501 Labor 279.060 Overhead 60.970 Total costs added into production in January $618,531 Work in process ending Units in process 23,100 Stage of completion for materials 50% Stage of completion for labor and overhead 10%