Bentley Enterprises uses process costing to control costs in the manufacture of Dust Sensors for the mining industry. The following information pertains to operations for November. (CMA Exam adapted)

Units
Work in process, November 1st 16,200
Started in production during November 102,000
Work in process, November 30th 24,200

The beginning inventory was 60% complete as to materials and 20% complete as to conversion costs. The ending inventory was 90% complete as to materials and 40% complete as to conversion costs.
Costs pertaining to November are as follows:
Beginning inventory: direct materials, $54,760; direct labor, $20,520; manufacturing overhead, $15,440.
Costs incurred during the month: direct materials, $470,000; direct labor, $184,880; manufacturing overhead, $393,160.
What is the equivalent unit cost for materials assuming Bentley uses first-in, first-out (FIFO) process costing?

a.$4.05.
b.$4.43.
c.$4.53.
d.$4.73.