If I sweat with this foundation on, what will happen?

So it is really hot where I am (100 degrees!) and I am new to foundation. Infact, tomorrow is going to be the first time ever that I am going to wear it to school. Anyways, I am using Physicians Formula Mineral Wear mineral foundation. When I start sweating ( and I sweat right in my homeroom!!!) what will happen to my makeup? Will it maybe smear? come off? I just dont want it to look cakey. I want to know if I sweat, will my makeup still look natural and give my skin coverage? I REALLY NEED TO KNOW!!