The books are closed yearly on December 31. Additional information is provided below: bad debt expense cis estimated to be $1, 600. Equipment is depreciated based on a 8-years life (no salvage value). Insurance expired during the year $3, 650. Interested accrued on notes payable $2, 050. Sales salaries and wages earned but not paid $2, 750. Advertising paid in advance $1, 100. Office supplies on hand $900, charged to supplies expense when purchased. Prepared an adjusted trial balance