Given the following data, calculate the cost of goods sold for the 04/15 sale using the weighted-average method. 1/1 Beginning inventory 50 units at $10 per unit 3/5 Purchases 30 units at $14 per unit 4/15 Sale 30 units at $30 per unit 5/30 Purchases 25 units at $15 per unit 10/25 Purchases 20 units at $16 per unit 11/15 Sale 60 units at $32 per unit 12/31 Ending inventory 35 units O a. $230 O b. $280 O c. $345 d. $600