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Coronado Company uses a periodic inventory system. Details for the inventory account for the month of January, 2018 are as follows: Balance, 1/1/18 160 $%4.00 Purchase, 1/15/18 150 5.10 Purchase, 1/28/18 150 5.70 Units Per unit price Total $640 765 855 An end of the month (1/31/18) inventory showed that 220 units were on hand. How many units did the company sell during January,2018 240 300 220 70