Chatting with friends made me aware some schools have already started finals. So I’m sorry to be late with this. But for those who need it here’s my ancient post on how to calculate the minimum score you need on the final to get the grade you want in the class. And for those who see my old prose style and recoil in horror I’m sorry. I was less experienced back then. Don’t look smug; you were too. But here’s a set of tables for common grade distributions, so you don’t have to do any calculations yourself. Just look up numbers instead.
With that information delivered, let me say once more: what you really need is to start preparing early, and consistently. Talk with your instructor about stuff you don’t understand, and stuff you think you understand, early on. Don’t give a line about the grade you need; that puts an inappropriate pressure on the instructor to grade you incorrectly. Study because it’s worth studying. Even if you don’t see why the subject is interesting, it is something that people smarter than you have spent a lot of time thinking about. It’s worth figuring out something of what they know that you don’t yet.