Chances of getting into NYU Stern or USC Marshall

I am currently a high school junior. I received a 1450 on the sat (690 reading and writing, 760 math). I am also the co captain of my robotics team and am in charge of collected finances and sponsors for my team. I am also the treasurer of my Coding Team. The main thing I am concerned about is my GPA. I have a 3.71 (which meets USC & NYU average) however I am a B math student with a C+ (79%). I am doing well in AP Macroeconomics and have a strong interest in business. What are the chances I get in even with my mediocre Math grades. Will my high SAT math make up for it? Does USC Marshall and NYU Stern make exceptions in the application process?

Side Question: How hard is it to transfer into Marshall or Stern as a USC student & NYU student (as in apply for an easier school and transfer in).