Need info about NHRA finals at Firebird track

Will be in Gilbert in Feb for a family vacation. Thinking of taking the wife and kids (8,11,13) to the NHRA finals at Firebird track. :

The gates open at 7:30 am and Sportsman racing starts at 8 am with the real races starting around 2 pm and a Nitro demo around 2:30 pm.

Had a couple questions:

- What is Sportsman racing?

- Don't want to spend the whole day there, but want to get there early enough to get decent seats for the pro races. What time will we have to show up to get decent seats?

- Checked the website and it looks like we could bring some small coolers in. Can we bring our own food and pop in the coolers?

Any other applicable infor or tips?

Thanks a lot?