Answer and Explanation:
The closing entries are shown below:
1. Service revenue $4,350
To Income summary 4,350
(Being the closing of service revenue is recorded)
For recording this we debited the sales revenue as it has normal credit balance so to close it we debited it and credited the income summary
2. Income summary $3,180
To Supplies Expense $870
To Insurance Expense $540
To Salaries and Wages Expense $1,770
(Being the closing of all expenses is recorded)
For recording this we debited the income summary and credited all expenses as it has normal debit balance so to close it we credited it
3. Income summary $1,170 ($4,350 - $3,180)
To Retained earnings $1,170
(Being the net income or loss is closed)
Since the revenue is more than the expenses so it would leads to net income and for recording this we debited the income summary and credited the retained earning so that the closing of the net income is recorded