On December 31, 2010 the Adjusted Trial Balance of the Grimm

On December 31, 2010 the adjusted trial balance of the Grimm Personnel Agency shows the following selected data:
Commission Receivable, $7,000
Commission Revenue, $70,000
Interest Expense, $10,500
Interest Payable, $2,500
Utilities Expense, $4,800
Accounts Payable, $2,400
Analysis indicates that adjusting entries were made for (a) $7,000 of employment commission revenue earned but not billed, (b) $2,500 of accrued but unpaid interest, and (c) $2,400 of utilities expense accrued but not paid.
Instructions
(a) Prepare the closing entries at December 31, 2010.
(b) Prepare the reversing entries on January 1, 2011.
(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 ($3,000) on January 15.
(e) Post the entries in (d) to the temporary accounts.
(f) What is the interest expense for the month of January 2011?