

Mathematicians. On a sphere, you can make a triangle that consists of three 90 degree angles, adding up to 270. A flat triangle will require that all angles add up to 180, i.e. 60, 60, 60.
Edit: I’m not a mathematician, and yet I know this. So this one could probably include anyone who has ever had a math teacher that covered spherical geometry.

Ron Swanson smirks at your comment.