85% was the A+ cut off, not the 40 ss cut off. Your study score isn't purely what you get on the exam although it plays the most important part. We had someone in our class that got a B in the exam (73%) and got a study score of 42.
Yes but you're rank 1 so only the exam score will only be relevant when determining your ss, unless someone ranked lower than you gets a higher exam score than you and boosts your score. The A+ cutoff for Media was the top 8%, which is in the 40 ss range. The top 9% of students get a study score of 40 or above.
As for that other student, that's very uncommon though. The only case I can think of is that he was rank 1 and he screwed the exam while someone else carried him.
I don't know why you'd be asking for predictions if you know so much already though?