Addison, Inc. uses a perpetual inventory system. Below is information about one inventory item for the month of September. Sep. 1 Inventory 20 units at $20 4 Sold 10 units 10 Purchased 30 units at $25 17 Sold 20 units 30 Purchased 10 units at $30 Use the information in the table to answer this question.If Addison uses the weighted average cost method, what is the inventory balance at the end of September? a. $1,500.00 O a. O b. $1,187.50 c. $1,375.00 O c. Od. $1,150.00