Department M had 2,500 units 52% completed in process at the beginning of June, 12,100 units completed during June, and 1,100 units 28% completed at the end of June. What was the number of equivalent units of production for conversion costs for June if the first-in, first-out method is used to cost inventories?

a.13,508 units

b.9,600 units

c.12,408 units

d.11,108 units