Problem 1: Write a program that keeps reading letter grade (A, B, C, D and F) until the user enters a non-valid one as a sentinel value. The program then should display the percentage of failed...

Hi! Please I want this written in Java programming language. Don’t forget to use documentation (comments) and proper indentation.


Extracted text: Problem 1: Write a program that keeps reading letter grade (A, B, C, D and F) until the user enters a non-valid one as a sentinel value. The program then should display the percentage of failed students. Sample Run: Enter a letter grade: B Enter a letter grade: F letter grade: C Enter a letter grade: A Enter a letter grade: C a letter grade: C Enter a letter grade: F Enter a letter grade: F Enter a letter grade: A Enter a letter grade: C Enter a letter grade: A Enter a letter grade: A Enter a letter grade: F Enter a letter grade: B Enter a letter grade: H Enter Enter The percentage of failed students is 28.57%