At the beginning of October, Bowser Company$$s inventory consists of $60$ units with a cost per unit of $$40.$ The following transactions occur during the month of October.

October $4$ Purchase $120$ units of inventory on account from Waluigi Company for $$50$ per unit, terms $2/10,$ n$/30.$

October $5$ Pay cash for freight charges related to the October $4$ purchase, $$600.$

October $9$ Return $20$ defective units from the October $4$ purchase and receipt of credit.

October $12$ Pay Waluigi Company in full.

October $15$ Sell $150$ units of inventory to customers on account, $$12,000.($Hint: The cost of units sold from the October $4$ purchase includes $$50$ unit cost plus $$6$ per unit for freight less $$1$ per unit for the purchase discount, or $$55$ per unit.$)$

October $19$ Receive full payment from customers related to the sale on October $15.$

October $20$ Purchase $90$ units of inventory from Waluigi Company for $$60$ per unit.

October $22$ Sell $90$ units of inventory to customers for cash, $$7,200.$

Required:

$1.$ Assuming that Bowser Company uses a FIFO perpetual inventory system to maintain its inventory records, record the transactions.

$2.$ Suppose by the end of October that the remaining inventory is estimated to have a net realizable value per unit of $$35.$ Record any necessary adjusting entry for lower of cost and net realizable value.

$3.$ Prepare the top section of the multiple$-$step income statement through gross profit for the month of October after the adjusting entry for lower of cost and net realizable value