The Kirkland Department of Delta Company began the month of December with beginning work in process of 4,000 units that are 80% complete as to materials and 20% complete as to conversion costs. Units transferred out are 12,000 units. Ending work in process contains 2,000 units that are 80% complete as to materials and 60% complete as to conversion costs. Compute the equivalent units of production for materials using the FIFO method?

a-10,000

b-12,000

c-12,400

d-10,400

e-12,800