On December 31, 2018 the Adjusted Trial Balance of the Yellin

On December 31, 2018 the adjusted trial balance of the Yellin Personnel Agency shows the following selected data:
Accounts Receivable, $8,000
Service Revenue, $60,000
Interest Expense, $10,500
Interest Payable, $3,500
Utilities Expense, $4,800
Accounts Payable, $2,700
Analysis indicates that adjusting entries were made for (a) $8,000 of employment commission revenue earned but not billed, (b) $3,500 of accrued but unpaid interest, and (c) $2,700 of utilities expense accrued but not paid.
Instructions
(a) Prepare the closing entries at December 31, 2018.
(b) Prepare the reversing entries on January 1, 2019.
(c) Enter the adjusted trial balance data in T-accounts. Post the entries in (a) and (b) and rule and balance the accounts.
(d) Prepare the entries to record (1) the collection of the accrued commission on January 8, (2) payment of the utility bill on January 10, and (3) payment of all the interest due ($4,000) on January 15.
(e) Post the entries in (d) to the temporary accounts.
(f) What is the interest expense for the month of January 2019?