Ferris company began january with 8,000 units of its principal product. the cost of each unit is $9. merchandise transactions for the month of january are as follows: purchases date of purchase units unit cost* total cost jan. 10 6,000 $ 10 $ 60,000 jan. 18 8,000 11 88,000 totals 14,000 148,000 * includes purchase price and cost of freight. sales date of sale units jan. 5 3,000 jan. 12 3,000 jan. 20 4,000 total 10,000 12,000 units were on hand at the end of the month.