The Assembly Department of​ Interface, Inc., manufacturer of​ computers, had 1 comma 500 units of beginning inventory in​ September, and 9 comma 000 units were transferred to it from the Production Department. The Assembly Department completed 4 comma 500 units during the month and transferred them to the Packaging Department. The weightedminusaverage method is used. Calculate the total number of units to account for by the Assembly Department.