I know sorry for that is just I felt a little bit uncomfortable because several people have been complaining about the videos and I think it’s good idea to value not only the downsides of the course ,but the good things and maybe try to start solving problems that maybe the instructor either forget to mention or just simply because it’s out date, doesn’t matter which one it is at least you will have some better understanding for the future ,nothing is perfect, but anyway thanks for the critics and I’m sorry david073 if I take this too personally!