3.21 Lab 4 Assignment 18 is continuation of assignment 1A where you are required to use if statements to improve the program Verify the entered data for soores are all between 0 and 100 if any of them is not valid (out of range or character is entered) print an error message and stop the program Once the average is calculated then assign a letter grade to the student based on the following table Average Grade 0-100A 80-89 70-79 : 60-69 D 0-59 F Develop a C++program based on the requirements stated on the assignments 1A and 18 Use the sample output posted below for submission on zyBooks