Refresh produces soft drinks and sodas. Production of 114,000 liters was started in February, 99,000 liters were completed. Material costs were $38,820 for the month while conversion costs were $24,180. There was no beginning work-in-process; the ending work-in-process was 40% complete. What is the cost of the product that remains in work-in-process?

a. $24,180.

b. $59,400.

c. $3,600.

d. $9,000.