This isn't really a question that can be answered thoroughly and accurately without fully explaining SAC statistical moderation and the calculation of study scores (which, to my knowledge, no one has on this forum).

The shortest accurate answer is that it really depends on what the top exam scores are in your cohort. Basically, if you are ranked 2nd or 3rd, each of the top quartile of exam scores within your cohort will influence your SAC GA score. It is often stated that if you are ranked (for example) 2nd your SAC GA score will be the 2nd highest exam score in your cohort, but this is a rough approximation only.

This is only your SAC GA score, of course. Your study score is a weighted average of each of your GA scores, including the exam. If you do brilliantly on the exam, that will of course push your study score up. It is entirely possible to be ranked below 1st and get a 50, even if no one else in your cohort gets a 50.