Problem
Develop a windows form inside visual studio named Grade With Method_3 that lets you do the following:
Enter a score (0-100) into a TextBox named txtScore, and compute the letter grade by clicking a button.
Use the scale 90, 80, 70 for A, B and C, respectively. The letter grade must be computed using a separate method named ComputeGrade. Call this method from the Click event of the button passing the score as a parameter to the method ComputeGrade program must return the letter grade to the calling program through a parameter. The calling program displays the data in a Label named lblLetterGrade
All must be done with windows form in C# language only and not C++ and screenshot the working program and post the entire code that was used to make the program followed by explanation toward the end.