8th problem from 3.06 sql exam

SELECT m.Model, m.Seats, v.Mileage
FROM Vehicles AS v
INNER JOIN Models AS m ON m.Id = v.ModelId
WHERE v.Id != ALL (
        SELECT VehicleId FROM Orders WHERE ReturnDate IS NULL
)
ORDER BY v.Mileage ASC, m.Seats DESC, v.ModelId ASC, m.Model ASC