Implement a class Quiz that implements the Measurable interface. A quiz has a score and a letter grade (such as B+). Use the implementation of the DataSet class in Section 9.1 to process a collection of quizzes. Display the average score and the quiz with the highest score (both letter grade and score).

Complete the following files:

Quiz.java

QuizTester.java

/** This program tests the Quiz and DataSet classes. */ public class QuizTester { public static void main(String[] args) { DataSet quizData = new DataSet(); Quiz q1 = new Quiz(89, "B+"); Quiz q2 = new Quiz(90, "A-"); Quiz q3 = new Quiz(73, "C"); quizData.add(q1); quizData.add(q2); quizData.add(q3); double avg = . . .; Quiz max = . . .; System.out.println("Average score: " + avg); System.out.println("Expected: 84.0"); System.out.println("Highest score: " + max.getScore()); System.out.println("Expected: 90.0"); System.out.println("Highest grade: " + max.getGrade()); System.out.println("Expected: A-"); } }

QuizTester2.java