Answer:
1. July 31 
Dr Supplies expense $9,120 
Cr Supplies $9,120
2. July 31 
Dr Rent expense $900 
Cr Prepaid rent $900
 
3. July 31 
Dr Salaries and wages expense $2480 
Cr Salaries and wages payable $2480
4. July 31 
Dr Depreciation expense $400 
Cr Accumulated depreciation - Building $400
5. July 31 
Dr Unearned service revenue $3,760 
Cr Service revenue $3,760
6. July 31 
Dr Miscellaneous expense $1,840 
Cr Miscellaneous expense payable $1,840
Step-by-step explanation:
Preparation of the adjusting entries at July 31 assuming that adjusting entries are made monthly.
 
1. July 31 
Dr Supplies expense $9,120 
Cr Supplies $9,120
($24,000-$14,880)
(Being To record supplies expense) 
2. July 31 
Dr Rent expense $900 
Cr Prepaid rent $900
(3,600*1/4)
(Being To record rent expense) 
3. July 31 
Dr Salaries and wages expense $2480 
Cr Salaries and wages payable $2480
(Being To record salaries and wages expense) 
4. July 31 
Dr Depreciation expense $400 
Cr Accumulated depreciation - Building $400
($4,800*1/12)
(BeingTo record depreciation expense) 
5. July 31 
Dr Unearned service revenue $3,760 
Cr Service revenue $3,760
(Being To record unearned service revenue) 
6. July 31 
Dr Miscellaneous expense $1,840 
Cr Miscellaneous expense payable $1,840
(Being To record maintenance and repairs expense)