Given the business use case:"New Trucks" runs a fleet of trucks in a rental business...

Given the business use case:

"New Trucks" runs a fleet of trucks in a rental business in the U.S. The majority of the trucks are owned; however, in some cases, "New Trucks" may procure other trucks by renting them from third parties to their customers. When trucks are leased, the internal source code is 'L'. When trucks are owned, the internal source code is 'O'. This identifies different accounts used for the journal entry. Customers sign a contract to initiate the truck rental for a specified duration period. The insurance fee is included in the contract and recognized over the rental period. For maintenance of the trucks, the "New Trucks" company has a subsidiary company "Fix Trucks" that maintains its own profit and loss entity. "New Trucks" and "Fix Trucks" are located in the same country and share a chart of accounts and accounting conventions.

How many ledgers are required to be set up?