Some of the multiple choice questions are really difficult and take long calculations, my teacher said the best advice is to just guess the answer for them, since they're only worth 1 mark it's best if you focus on the other questions which give marks.
If you want an A you will only need 56 marks in total in the exam (if you scored at least 14 marks in the assignment) so guessing a few questions in the multiple choice if your low on time is best.
Remember you can write as much as you like on the multiple choice question sheet for your calculations or notes etc., you can even take the multiple choice questions home with you so it is wise to use the space you're given since doing the problem solving in your head is difficult.