Department S had 700 units 70% completed in process at the beginning of the period, 8,100 units completed during the period, and 1,000 units 37% completed at the end of the period. What was the number of equivalent units of production for the period for conversion if the first-in, first-out method is used to cost inventories? Assume the completion percentage applies to both direct materials and conversion cost.

a.8,980

b.7,610

c.7,980

d.7,400