Volkan Inc. manufactures three different types of mattresses, standard, deluxe and super deluxe. For the year 2008, it manufactured 10,000 units of standard, 5,000 units of deluxe and 5,000 units of super deluxe. The total manufacturing overhead predicted for the year was $256,400. If the firm allocated the overhead costs based on the number of units of production, how much overhead cost was allocated per unit of standard mattress?

a.$10,000

b.$25.64

c. $12.82

d. $12,820