Explain what is Multilevel Inheritance ?

The Car-Motorcycle-MotorVehicle instances showed single-level inheritance. There's nothing to stop you from going next. You can describe subclasses of cars for compacts, station wagons, sports coupes and more. For instance, this class describes a compact as a car with two doors:

public class Compact extends Car {

// constructors
public Compact(String licensePlate, double maxSpeed,
String make, String model, int year, int numberOfPassengers) {
this(licensePlate, 0.0, maxSpeed, make, model, year, numberOfPassengers);
}

public Compact(String licensePlate, double speed, double maxSpeed,
String make, String model, int year, int numberOfPassengers) {
super(licensePlate, speed, maxSpeed, make, model,
year, numberOfPassengers, 2);
}
}
Compact not only inherits from its immediate superclass, Car, but also from Car's superclass, MotorVehicle. Therefore the Compact class also has a make, a model, a year and so on. There's no limit to this chain of inheritance, by getting more than four or five classes deep creates code excessively complex.