Accounts	debit	credit
Cash	26,100
Supplies	6,700
Notes receivables	10,000
Land	85,000
Account payable		12,300
Common stock		106,000
Retained earnings		29,900
Service revenue		131,800
Salaries expense	70,900
Utilities expense	24,200
Supplies expense	15,700
Sales discount	100
Allowance for Uncollectible accounts	?
Accounts receivable	42,000

I cant figure the allowance for Uncollectible Accounts please help