What are the explanations for the answers to these questions?

39) d

40) b

41) c

39. Fo+2017, the average time (360 day year) for Red Company to sell its inventory was: Year Cost of Goods Sold Ending Inventory Red Company 2015 $225 $25 2016 $234 $26 2017 $192 $22 a. 39.8 days b. 40.0 days c. 41.2 days d. 45.0 days 40. The control principle of not having the same person record a purchase and sign payment is known as a. proper authorization. b. separation of duties. c. independent internal verification. d. rotation of duties. 41. An aging of accounts receivable estimates a total $4,500 will become uncollectible. If Allowance for Doubtful Accounts has a $1,600 credit balance, the bad debt expense will be a. $6,100. b. $4,500. c. $2,900. d. $1,600