Foster Company initially records prepaid and unearned items in income statement accounts. Given Foster Company’s practices, what is the appropriate adjusting entry for each of the following at November 30, 2020, the end of the company’s first accounting period?

a. There are unpaid salaries of $3,000.

b. Unused office supplies of $800 were counted at year-end. There was no beginning balance in office supplies.

c. Earned but unbilled consulting revenue of $2,300 was discovered.

d. It was determined that there was unearned revenue of $4,200.