Aqua Corporation uses the weighted average method in its process costing system. Cost data for its work in process department follow:

Materials Conversion
Beginning work in process $67,000 $48,000
Costs added during the period $125,000 $225,000

Assuming equivalent units of production for materials are 90,000 and for conversion are 20,000, the cost per equivalent unit for materials during the period is closest to: ________

a. $3.89
b. $1.75
c. $1.39
d. $2.13