Cardoza Company recently tried to improve analysis of its manufacturing process. Units started into production equaled 5600, units transferred out equal 5600 and ending units work in process equal 400. There was no beginning inventory. Materials are at applied at the beginning of the process. How much is the direct materials cost per unit if ending work in process was 25% and total conversion costs equal $18,000?

a. $ 3.00

b. $ 3.21

c. $ 3.00

d. $ 3.16