The debits to Work in ProcessAssembly Department for May, together with data concerning production, are as follows: May 1, work in process: Materials cost, 3,000 units $?,500 Conversion costs, 3,000 units, 50% completed 5,000 Materials added during May, 10,000 units 25,500 Conversion costs during May 31,100 Goods nished during May, 11,500 units 0 May 31 work in process, 1,500 units, 50% completed 0 All direct materials are placed in process at the beginning of the process, and the rst-in, rst-out method is used to oust inventories. The materials cost per equivalent unit for May is Oa. $2.55 Ob. $3.11 Oc. $3.1m l Co. $2.23