I need help in C#

Ask the user to input their grade percentage (e.g. the use will enter 98 if they had an overall grade of 98% in their course) for their Accounting, Marketing, Economics and MIS courses. Assume each course is worth 3 credit hours. Once you have all of their grades output what letter grade they earned for each course (e.g. Your letter grade for {Accounting/Marketing/whichever one you are outputting} is {A/B/C/D/F}). After you have output all of their letter grades, output their overall GPA for the semester using the formula:

Letter Grade	Point Value for Grade
A	4.00
B	3.00
C	2.00
D	1.00
F	0.00