Good evening. We had a bit of an intervention with my daughter about the class she got the C- in and made her email the teacher which turned out to be a grad student and not a professor. We had her be courteous but ask for explanation as to why she was taken down to that grade when he never even gave her a score in her final yet. I don’t know that it will do any good but we may ask to speak with the professor or whoever is supervising this grad student.