What would be the adjusting journal entry (what account to debit and credit, and the dollar amount) in each of the following independent scenarios (no narrative response required, only the journal entry and amounts):

a. Northern Company uses the Percent-of-Sales method to estimate uncollectible accounts, estimating 5% of their sales as bad debts. October sales totaled $600,000. The Allowance for Bad Debt account has a credit balance of $2,000 on Sept. 30 (the previous month-end). What is the adjusting entry at the end of October?

b. Southern Inc. uses the Percent-of-Receivables method to estimate uncollectible accounts, estimating that 4% of their Total Receivables will be uncollectible. As of July 31, the total A/R balance is $200,000. The Allowance for Bad Debt account has a credit balance of $1,000 on June 30 (the previous month-end). What is the adjusting entry at the end of July?

c. Western Corp. uses the Aging-of-Receivables method to estimate uncollectible accounts. On Dec. 31, the company analyzes their A/R Aging report and estimates that $8,000 will be uncollectible. The Allowance for Bad Debt account has a debit balance of $2,000 on Nov. 30 (the previous month-end). What is the adjusting entry at the end of December?