Zippy Cola uses a process costing system with two processing departments, Mixing and Packaging Departments. Work in process inventories are reduced to zero each month. In May, the Mixing Department incurred manufacturing costs of $20,000. A total of 68,750 bottles of cola were transferred to the finished goods warehouse during the month Zippy sold 10,000 bottles in the month of May $10,000. What was the cost of goods sold for that month? O a. $4,909 O b. $4,000 O c. $2,000 O d. $27,500