My question regard the calculation of grade point average in case of an F grade. Are the units or credit hours of the course with F grade included in the calculation of the grade point average. Now when the F grade is removed by retaking the course (assume B grade was earned in the repetition) what grade would be assigned to this course, and would it be included in the calculation of the grade point average.

Yes, the F is factored in as 0 grade points. The B would cause the gpa to be recalculated.