and can you please explain. Thank you!

Frank Inc., has the following information available: At the beginning of the period, there were 579 units in process that were 46 percent complete as to conversion costs and 100 percent complete as to direct materials costs. During the period 4, 951 units were started and completed. Ending inventory contained 369 units that were 22 percent complete as to conversion costs and 100 percent complete as to materials costs. (Assume that the company uses the FIFO process cost method.) What was the cost of completing a unit during the current period? Select the correct answer. $31.61 $26.94 $4.67 $390.25