C#

Create a form that lets user to do the following:

- Enter a score (0-100) and a name into two different TextBoxes and compute the letter grade by clicking a button

Use the scale 90,80,70,60 for A, B, C and D, respectively. Anything below 60 should be F. The Click event handler of the button must call three separate methods, corresponding to the three subtasks described below:

1. A method named ValidScore that gets the score from the TextBox, validates the score and passes the valid score to the click event handler.

2. A second method named GetLetterGrade that computes the letter grade. Pass the score from the calling program to Grade. The method must return the letter Grade back.

3. A third method that displays the name and letter grade. Pass the name and letter grade as parameters to this method.