Flagston company uses a weighted-average process-costing system. Company records disclosed that the firm completed 40,000 units during the month and had 10,000 units in process at month-end, 20% complete. Conversion costs related to the beginning work-in-process inventory amounted to $231,000, and amounts incurred during the current month totaled $900,000. If conversion is incurred uniformly throughout manufacturing, Flagston's equivalent-unit cost is:

a) $7.00

b) $7.88

c) $8.40

d) $9.00