Given the UML diagram outlined below, which illustrates an Employee class that implements Comparable and contains an inner class EmployeeCompare that implements Comparator. You are required to: a) Implement the Employee class to allow comparison of Employee objects based on their names through the compareTo method() and by their ID numbers through the inner class EmployeeCompare. [15 Marks] b) Write a driver class which: creates an ArrayList containing two employee objects and calls Collections.sort to sort the list. creates an instance of EmployeeCompare and calls Collections.sort with the EmployeeCompare instance as a second argument Implement the classes outlined in the UML diagram above, ensuring the classes are serializable. Note: Employees are paid a rate of 15 per hour. The Employee class contains the following abstract method: abstract double earnings(); [15 Marks] b) Write a driver class that creates a LinkedList of employees. Populate the list with two instances of the subclass, then calculate and display the earnings. Finally, serialize the list