please explain

2. Use this information for the month of June. June 1 Beginning Inventory 10 units @ $120 5 Purchase 60 units @ $112 14 Sale 40 units 21 Purchase 30 units @ $116 22 Sale 28 units 23 Purchase 20 units @ $180 24 Sale 25 units Assuming that a periodic inventory system is used, what is cost of goods sold on a LIFO basis? $11.896 Assuming a periodic system, what is ending inventory using FIFO? $4,412 Assuming a periodic system, what is ending inventory using weighted average? $3.375