Ferris Company began January with 7,000 units of its principal product. The cost of each unit is $7. Merchandise transactions for the month of January are as follows: Purchases
Date of Purchase Units Unit Cost* Total Cost
Jan. 10 6,000 $8 $48,000
Jan. 18 7,000 9 63,000
Totals 13,000 111,000

Includes purchase price and cost of freight.

Sales
Date of Sale Units
Jan. 5 3,000
Jan. 12 1,000
Jan. 20 4,000
Total 8,000

12,000 units were on hand at the end of the month.

Required:
a. Calculate January's ending inventory and cost of goods sold for the month using FIFO, periodic system.
b. Calculate January's ending inventory and cost of goods sold for the month using each of the following alternatives:

1. FIFO, periodic system.
2. LIFO, periodic system.
3. LIFO, perpetual system.
4. Average cost, periodic system.
5. Average cost, perpetual system.