Please explain the process with the calculation

26. Darvin Company uses the weighted-average method in its process costing system. The first processing department, the Welding Department, started the month with 20,000 units in its beginning work in process inventory that were 10% complete with respect to conversion costs. The conversion cost in this beginning work in process inventory was $7,000. An additional 63,000 units were started into production during the month. There were 10,000 units in the ending work in process inventory of the Welding Department that were 10% complete with respect to conversion costs. A total of $237,600 in conversion costs were incurred in the department during the month. What would be the cost per equivalent unit for conversion costs for the month? (Round off to three decimal places.) A) $3.255 B) $3.771 C) $3.500 D) $3.305