Answer:
a-Dec-31. Dr Utility expense  485
          Cr  Utility bills payable  485
b-Jan-11.  Dr Utility bills payable  485
            Cr Cash          485
c-Dec-31. Dr Salary expense  3990
        Cr  Salary payable         3990
d-Dec-31. Dr bank 51600
         Cr  Loan payable  51600
e-Dec-31 Dr Interest expense  215
          Cr interest payable   215
f-Dec-31 Dr Account receivable  340
         Cr  Service revenue  account   340
g-Dec-31. Dr Cash  6840
         Cr Advance Rent   6840
Explanation:
a-Utility expense incurred for the m/o Dec will be paid in Jan.
c- Salaries of 3990 will be paid on Jan of 4 days.
e-Interest expense for the m/o Dec will be (51600*5%=2580/12=215.
f-The service fee is receivable which will be paid on Jan.
g- Advance rent is received from client.