Answer and Explanation:
The Journal entry is shown below:-
1. Rent expense Dr, $1,920 ($5,760 × 2 ÷ 6)
       To Prepaid rent $1,920
(Being rent expense is recorded)
2. Unearned revenue Dr, $450
      To Service revenue $450
(Being service revenue is recorded)
3. Salary expense Dr, $600
      To Salary payable $600
(Being salary expense is recorded)
4. Supplies expense Dr, $2,120 ($1,100 + $1,700 - $680)
        To Supplies $2,120
(Being supplies expense is recorded)