3. Answer query optimization questions for the following SQL statement

SELECT OrdNo, OrdDate, Vehicle.ModelNo FROM Customer, Order, Vehicle

WHERE CustBal > 5000

AND Customer.CustNo = Vehicle.CustNo AND Vehicle.SerialNo = Order.SerialNo

3.1. List the possible orders to join the Customer, Order, and Vehicle tables.

3.2. For one of these join orders, make an access plan. Assume that Btree indexes only exist for the primary keys, Customer.CustNo, Order.OrdNo, and Vehicle. SerialNo.