do not worry about GPA. they dont care so much about that or class rank. if one were to hold more weight, class rank is bigger. i have a 3.2 and im going. just score well on SAT and youre good. but max out everything if you have a lower GPA. SAT is 50% of the entire process.
They do not mix and match. But i do advise you taking the SAT again. im a senior getting ready to go and my SAT is 650 CR 660 W 670 M. so keep taking. i took it five times.