For the Mixing Department at Gretczko Company, unit material cost is $6 and unit conversion cost is $9. Materials are added at the beginning of the process. If there are 55 units in ending work in process that are 75% complete with conversion costs, the costs assigned to ending inventory are: O a. $ 618.75 O b. $ 701.25 c. $825.00 O d. $ 371.25