The debits to Work in Process-Assembly Department for May, together with data concerning production, are as follows: May 1, work in process: Materials cost, 3,000 units Conversion costs, 3,000 units, 50% completed Materials added during May, 10,000 units Conversion costs during May Goods finished during May, 11,500 units $8,100 5,700 27,200 30,000 0 0 May 31 work in process, 1,500 units, 50% completed All direct materials are added at the beginning of the process, and the first-in, first-out cost flow method is used. The materials cost per equivalent unit for May is a. $2.37 b. $3.00 Oc. $3.81 Od. $2.72