Watson Limited prepares monthly financial statements. Below are listed some selected accounts and their balances on the 30 September 2023 trial balance before any adjustments have been made for the month of September 2023. Watson Limited Unadjusted Trial balance (selected accounts) 30 September 2023 Office supplies $2,700 Dr Prepaid insurance $5,400 Dr Office equipment $15,000 Dr Accumulated depreciation - office equipment $1,000 Cr Revenue received in advance $1,200 Cr (Note: Debit column does not equal credit column because this is a partial listing of selected account balances.) An analysis of the account balances by the company's accountant provided the following additional information: Ref. Ref-1. A physical count of office supplies revealed $1,200 on hand on 30 September 2023. Ref-2. A two-year insurance policy was purchased on 1 June 2023 for $5,400. Ref-3. Office equipment depreciates $6,000 per year on a straight line basis. Ref-4. The amount of rent received in advance that remains unearned at 30 September 2023 is $500. Required: Using the above additional information, prepare the adjusting journal entries by number reference (Ref) that should be made by Watson Limited on 30 September 2023. You may omit journal