At December 31, Fareed Coffee Company reports the following results for its calendar year.

Cash sales	$	912,000
Credit sales		312,000

Its year-end unadjusted trial balance includes the following items.

Accounts receivable	$	137,000	debit
Allowance for doubtful accounts		6,200	debit

Prepare the adjusting entry to record bad debts expense assuming uncollectibles are estimated to be (a) 3% of credit sales, (b) 1% of total sales and (c) 6% of year-end accounts receivable.