On January 1, 2014, the Allowance for Doubtful Accounts has a credit balance of $18,000. During 2014, $30,000 of uncollectible accounts receivable were written off. An ageing schedule indicates that uncollectible accounts are $20,000 at the end of 2014. What is the required adjustment to the allowance for doubtful accounts at December 20147 $32,000 $2,000 Ob $8,000 $20,000