C$++$ Exercise $1$: Run the program three times using $80,55$ and $60$ for the average. What happens when you input $60$ as the average? Modify the first if statement so that the program will also print $$You Pass$$ if the average is greater than or equals $60.$ Exercise $2$: Modify the program so that it uses an if$/$else statement rather than two if statements. Exercise $3$: Modify the program from Exercise $2$ to allow the following categories: Invalid data $($data above $100),$A$$ category $(90100),$B$$ category $(8089),$You Pass$$ category $(6079),$You Fail$$ category $(059).$ What will happen to your program if you enter a negative value such as $-12?$