Draw an inheritance hierarchy for students at a university similar to the hierarchy shown in above fig. use student as the superclass of the hierarchy, then extend Student with classes undergraduateStudent and graduateStudent. Continue to extend the hierarchy as deep (i.e., as many levels) as possible. For example, freshman, sophomore, junior and senior might extend undergraduateStudent, and doctoralStudent and mastersStudent might be subclasses of graduateStudent. After drawing the hierarchy, discuss the relationships that exist between the classes. Write proper code to implement the inheritance.