We need to implement a program that allows a teacher to track and manipulate data for a course. The gradebook needs to perform the following functions:

Record an unknown number of grades.

Find the maximum grade earned

Find the minimum grade earned

Find the average of all of the grades.

To do this, you need to implement the GradeBookInterface. The teacher should be able to enter as many grades as they would like. When they enter a grade less than 0, this indicates they have entered all the grades desired, print the maximum and minimum values entered. In addition, print out the average of the grades entered. You must use the methods you implement in the GradeBook class. Your average should be reported to two decimal places.

Sample output:

Enter grade number 1. Enter a negative number to quit.

100

Enter grade number 2. Enter a negative number to quit.

105

Enter grade number 3. Enter a negative number to quit.

23

Enter grade number 4. Enter a negative number to quit.

50

Enter grade number 5. Enter a negative number to quit.

-1

The maximum grade entered is: 105.0

The minimum grade entered is: 23.0

The average score is 69.50