Starter 6-2 (similar to) Citerion Company has the following items in its inventory on August 1. Serial Number Cost 6X6A1 $ 10,100 10.900 6Y6M5 6B6D8 8.900 6R7R5 26.000 The company uses the specific-unit-cost method for costing inventory. During August, it sold units 6X6A1 and 6B6D8 for $25,000 each and purchased unit 6A7M6 for $13,000. Calculate the gross margin for the month of August. The gross margin for the month of August is $