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Brickman Corporation uses the allowance method to account for uncollectible receivables. At the beginning of the year, Allowance for Bad Debts had a credit balance of $1,000. During the year Brickman wrote off uncollectible receivables of $2,100. Brickman recorded Bad Debts Expense of $2,700. What is Brickman's year- end balance in Allowance for Bad Debts? a. $1,600 b. $4,800 c. $3,700 d. $600