No makeup exams are given. If you have a valid written excuse, such as a doctor's note, then your grade will be based on a weighted average of the remaining exams. If you miss a midterm then your two remaining midterms will count for all of your midterm grade. If you miss the final then your midterms will determine all of your exam grade.
If you do not have a valid written excuse then your final course grade will be lowered by half a grade. For example, if your weighted grades would give you an A for the course you will receive a B+ and if they would give you a B+ you will receive a B. Your exam grade will be based on a weighted average of the remaining exams as described above.