Chance of rescinding ED Northwestern app?

<p>So I got into NU ED, my grades werent great to start out with, I got a bunch of Bs 9th-10th grade, and all As 1th but hardest classes 12th. If I make Bs midterms, how many, out of 7 would i ahve to get to get my app rescinded? I'm worried b/c my grades are borderline</p>