21. Assume the following information: Milling Department Materials Cost of beginning work in process Inventory $10,000 290,000 Total cost $300,000 Costs added during the period Conversion $ 15,000 Total $25,000 391,000 $406,000 681,000 $706,000 If the equivalent units of production for conversion is 5,000 units using the weighted-average method, then what is the cost per equivalent unit for conversion? (Round your final answer to nearest whole dollar amount.) A) $81 B) $78 C) $141 D) $60