i dont understand about 12-5&12-6

12-5 Leland Hotels has accounts receivable of $98,100 at March 31. An analysis of the accounts shows the following: Credit terms are 2/10,n/30. On March 31 , Allowance for Doubtful Accounts has a credit balance of $1,200 prior to adjustment. The company uses the percentage of receivables basis for estimating uncollectible accounts. The company's estimate of bad debts is as follows: Instructions (a) Determine the total estimated uncollectibles. (b) Prepare the adjusting entry at March 31 to record bad debts expense. 12-6 On December 31,2008 , Crawford Resorts estimated that 1.5 percent of its net sales of $400,000 would become uncollectible. The company recorded this amount as an addition to Allowance for Doubtful Accounts. On May 11, 2009, Crawford Co. determined that Kevin Hayes's account was un collectible and wrote off $1,100. On June 12, 2009, Hayes paid the amount previously written of Instructions (A) Prepare the journal entries on December 31, 2008; May 11, 2009; and June 12, 2009