Chapter 9, Problem 5PC

Course Grades

In a course, a teacher gives the following tests and assignments:

• A lab activity that is observed by the teacher and assigned a numeric score.
• A pass/fail exam that has 10 questions. The minimum passing score is 70.
• An essay that is assigned a numeric score.
• A final exam that has 50 questions.

Write a class named CourseGrades. The class should have a GradedActivity array named grades as a field. The array should have four elements, one for each of the assignments previously described. The class should have the following methods:

setLab:	This method should accept a GradedActivity object as its argument. This object should already hold the student’s score for the lab activity. Element 0 of the grades field should reference this object.
setPassFai1 Exam:	This method should accept a PassFailExam object as its argument. This object should already hold the student’s score for the pass/fail exam. Element 1 of the grades field should reference this object.
setEssay:	This method should accept an Essay object as its argument. (See Programming Challenge 4 for the Essay class. If you have not completed Programming Challenge 4, use a GradedActivity object instead.) This object should already hold the student’s score for the essay. Element 2 of the grades field should reference this object.
setFinal Exam:	This method should accept a FinalExam object as its argument. This object should already hold the student’s score for the final exam. Element 3 of the grades field should reference this object.
toString:	This method should return a string that contains the numeric scores and grades for each element in the grades array.

Demonstrate the class in a program.