write the following programs: Ram.java, Truck.java, LandVehicle.java and Vehicle.java.

public class Ram extends Truck { public static void main(String[] args) {

 // your implementation } 

 public Ram() { // your implementation 

} }

public class Truck extends LandVehicle { public Truck() { 

 // your implementation } 

 public Truck(String s) { // your implementation 

} }

public class LandVehicle extends Vehicle { public LandVehicle() { 

 // your implementation } 

}

public class Vehicle { public Vehicle() { 

 // your implementation