Write a C program that calculates and prints the average of several grades entered by the user. The program should first prompt the user to enter the number of grades to process (at least 2 grades must be entered by user!) . It should then prompt the user for each grade. As each grade is entered, the program should ensure that the grades entered are in the grade range of zero to 100. If the grade is not in that range, an error message should be displayed (as shown below), and the user should be re-prompted for a grade. Any bad grades entered should not be included in the average calculation. Once all values are entered, the program should calculate and print the average of all of the positive values entered, rounded to the nearest whole number. At the end display a message for the appropriate letter grade as in our course in the 'How you will be graded' section in the 'Syllabus' section of the notes. This program will feature the if statement as well as programming techniques for data validation. I call it a trap loop. It traps the user into entering valid data.

The dialog with the user should be as follows:

This program calculates the average of as many grades you wish to enter.

First, enter the number of grades to process: 4

Now enter the 4 grades to be averaged.

Enter grade #1: 100

Enter grade #2: 80

Enter grade #3: -20

*** Invalid entry. Grade must be 0 to 100. ***

Enter grade #3: 25

Enter grade #4: 54

The average of the 4 grades entered is 65

You have a letter grade of D

Hints/ Other Requirements:

* This program requires variables of type int and float.

* Use printfand scanf statements to first prompt the user for the number of grades to be processed.

* This program requires loop structure(s) (for, while or do -- your choice).

* The loop requires some a printf and scanf statement to prompt user for a grade.

* The loop also requires a selection structure (if, or if else) statement to check for bad data values.

* The selection structure requires a printf statement to output error message if improper grade.

* The program requires an accumulator to keep track of the sum of good grades entered.

* Once all grades are entered, determine average rounded to the nearest whole number, and then a printf statement to display the average, and a printf statement to display the appropriate letter grade: Use the grading chart from the "How You Will be Graded" section to assign the letter grades.