Answer:
1. Dr    Cash    2400
      Cr       Deferred revenue   2400
  (To record advance received for office space,which is not earned yet)
2.a)Dr Prepaid insurance  11280
               Cr Cash                   11280
( To record purchase of insurance )
   b)  Dr  Insurance expense 5640
                      Cr prepaid insurance     5640
       ( To record insurance expired) 
3. Dr salary expense       1400
         Cr  Salary payable          1400
 ( To record salary expense for the m/o December)
4. Dr Cash    7000
          Cr   Loan payable      7000
        ( Acquire loan from bank)
5. a) Dr Interest expense  1680
               Cr interest payable          1680
   ( To record interest expense of 2 months )    
6. a)Dr supplies  1800
          Cr       Cash             1800
          (Supplies purchased)
    b) Dr Supplies expense   1460
               Cr     Supplies                   1460
    (Adjusting entry of supplies used)
Explanation:
2. Insurance for the month = 11280/12= 940. For 6 months= 940*6=5640
4. yearly interest rate = 7000 *12% = 840. two month interest = 840 *2= 1680