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Question from the College Board

public class StudentRecord
{
        private int[] scores;
	public StudentRecord(int[] scores) {
		this.scores = scores;
	}
	/**
	 * returns the average (arithmetic mean) of the 
	 * whose subscripts are between first and last,
	 * precondition: 0 <= first <= last < scores.length
	 */
	public double average(int first, int last)
	{
		// part (a) 
		return 0D;
	}
	/**
	 * returns true if each successive value in scores is greater
	 * than or equal to the previous value;
	 * otherwise, returns false
	 */
	public boolean hasImproved()
	{
		//part (b)
		return false;

	}
	/**
	 * if the values in scores have improved, returns the average
	 * of the elements in scores with indexes greater than or equal
	 * to scores.length/2; 
	 * otherwise, returns the average of all of the values in scores
	 * 
	 */
	public double finalAverage()
	{
		// part (c)
		return 0D;
	}
        public static void main (String[] args)
        {
         //three different ways to make our int arrays
         int[] a1={50, 50, 20, 80, 53}; 
         int a2[]={20, 50, 50, 53, 80};    
         int[] a3=new int[4];
         a3[0]=20;
         a3[1]=a3[2]=50;
         a3[3]=80;

         StudentRecord s1=new StudentRecord(a1);
         StudentRecord s2=new StudentRecord(a2);
         StudentRecord s3=new StudentRecord(a3);

         System.out.println("s1 improved? "+ passFail(false, s1.hasImproved()));
         System.out.println("s2 improved? "+ passFail(true, s2.hasImproved()));
         System.out.println("s3 improved? "+ passFail(true, s3.hasImproved()));

         System.out.println("\ns1 average(0,1): "+ passFail(50, s1.average(0, 1)));
         System.out.println("s2 average(1,2): "+ passFail(50, s2.average(1, 2)));
         System.out.println("s3 average(0,2): "+ passFail(40, s3.average(0, 2)));


         System.out.println("\ns1 final average: " + passFail(50.6, s1.finalAverage()));
         System.out.println("s2 final average: " + passFail(61.0, s2.finalAverage()));
         System.out.println("s3 final average: " + passFail(65.0, s3.finalAverage()));
        }

 }

Driver to test it out:

public class AverageTester{

    public static void main (String[] args)
    {
     //I made 3 integer arrays in  three different ways!
     int[] a1={50, 50, 20, 80, 53};
     StudentRecord s1=new StudentRecord(a1);

     int a2[]={20, 50, 50, 53, 80};
     StudentRecord s2=new StudentRecord(a2);
     int[] a3=new int[4];
     a3[0]=20;
     a3[1]=a3[2]=50;
     a3[3]=80;
     StudentRecord s3=new StudentRecord(a3);

     System.out.println("s1 improved? (should be false):"+ s1.hasImproved());
     System.out.println("s2 improved? (should be true):"+ s2.hasImproved());
     System.out.println("s3 improved? (should be true):"+ s3.hasImproved());

     System.out.println("s1 average? (should be 50.6):"+ s1.finalAverage());
     System.out.println("s2 average? (should be 61.6):"+ s2.finalAverage());
     System.out.println("s3 average? (should be 65.0):"+ s3.finalAverage());
    }

}