what is the solution to all parts

Refer to the information in Exercise 6-7 and assume the periodic inventory system is used. Determine the costs assigned to ending inventory and to cost of goods sold using (a) FIFO and (b) LIFO. Then (c) compute the gross margin for each method

date activities units acquired at cost units sold at retail

jan 1 beginning inventory 200 units @ $10 = 2,000

jan 10 sales 150 units @ $40

Mar 14 purchase 350 units @ $15 = 5,250

mar 15 sales 300 units @ $40

July 30 purchase 450 units @ $20 = 9,000

oct 5 sales 430 units @ $40

oct 26 purchase 100 units @ $25 = 2,500

totals 1,100 units $18,750 880 units