Listed below are selected transactions for the Gotham City Garbage Service, which is accounted for in an Enterprise Fund. All amounts are in thousands of dollars.

Transactions:

1. Services of $8,250 were provided and billed to outside customers.
2. Services of $1,500 were provided and billed to the General Fund.
3. $1,500 was collected from other funds, and $7,500 was collected on account.
4. $100 of accounts receivable were written off as uncollectible.
5. Estimated bad debts for the year were $220.

Requirements:

Prepare the journal entries required in the Enterprise Fund. If no entry is required, state "No entry required" and explain why.