Error(s), warning(s):

source_file.java:7: error: class Vehicle is public, should be declared in a file named Vehicle.java
public class Vehicle{
       ^
source_file.java:79: error: class Truck is public, should be declared in a file named Truck.java
public class Truck extends Vehicle {
       ^
source_file.java:159: error: class Car is public, should be declared in a file named Car.java
public class Car extends Vehicle {
       ^
source_file.java:205: error: class Unit6Assign is public, should be declared in a file named Unit6Assign.java
public class Unit6Assign {
       ^
4 errors