help! I added most of the expenses except income and interest expense and subtracted it by the gross profit but still cant get the correct answer

Computing Gross Profit and Operating Income Following is an excerpt from the Packer Inc. year-end trial balance dated December 31, 2020. Credit $126,000 1,800 5,040 Selected Adjusted Trial Balance Amounts Acct. No. Description Debit 400 Sales revenue 402 Consulting revenue 404 Gain on sale of investments 510 Cost of goods sold $45,000 511 Selling expense 19,800 Salaries expense 5,400 Rent expense 3,600 Insurance expense 900 528 Depreciation expense 1,800 530 Research and development expense 9,000 Loss on sale of investments 3,240 Interest expense 900 542 Income tax expense 3,510 512 526 540 Required a. Compute gross profit for 2020. b. Compute operating income for 2020. $ $ 81,000 40,500 x Check