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A company had 1,000 units in work in process at the start of a period, started 5,000 units into production during the period, and had 800 units in work in process at the end of the period and were 90% complete with respect to conversion costs. The total work done this period in equivalent units of conversion cost was: a. 5,800 b. 5,920 C. 6,800 d. None of the above