Hey Thai-Son. It's
usually a TA that does tutorials, but not always. For one of my math courses last year it was actually the prof who did the tutorials, and I was in the same position as you are: I had a different prof for tutorial than I had for lectures. I would try to change it to the same prof if I were you, only because they may cover the course materials in a slightly different order or cover certain chapters at a different pace. Hope this helps
and have a good first year at Mac !