Write a program where: 1. The user enters a number from 0 to 100. 2. If a number below zero or above 100 is entered, an error message appears and the user tries again. If the grade is from 90% to 100%, set grade to "A". If the grade is from 80% to 89.99%, set grade to "B". If the grade is from 70% to 79.99%, set grade to "C". If the grade is from 60% to 69.99%, set grade to "D". If the grade is from 0% to 59.99%, set grade to "F".

This is for C#.