Answer and Explanation:
The adjusting entries are shown below:
1. Interest expense [$11,400 × 9% × 4 ÷ 12]	$342  
     To Interest payable  $342
(being accrued interest expense is recorded)  
2. Supplies expense [$2,200 - $820]	$1,380  
      To Supplies  $1,380
[Being supplies expense is recorded]  
3. Depreciation expense $1,200  
      To Accumulated depreciation-Equipment $1,200
[Being depreciation expense is recorded]  
4 Insurance expense [$3,960 × 7 ÷ 12] $2,310  
           To Prepaid insurance  $2,310
[being insurance expense is recorded]  
5  Unearned service revenue $7,000  
              To Service revenue $7,000
[Being revenue from unearned is recorded]  
6 Accounts receivable	$4,200  
          To Service revenue  $4,200
[Being accrued service revenue is recorded]  
7 Salaries expense [$5,400 ×  3 ÷ 5] $3,240  
           To Salaries payable $3,240
[being accrued salaries expense is recorded]