C++ Function Tasks . . Write a code which accept marks of three subjects as argument and return CGPA on the basis of marks. Write a code which accept marks of one subject as argument and return grade on the basis of marks. Write a function which accept two integers as arguments and return their GCD. Write a function which accept character argument and check if it is alphabet or not, if character is alphabet then check if it is in upper case or lower case. Convert uppercase to lowercase and vice versa and return converted value to the main. . Write a function which accept character argument and find if it is vowel or not Write a function named hollow_diamond which print following pattern and return number of rows in pattern