Actually, the cohort class for nursing schools changes ever year. This is why folks tell you to shoot for a minimum of a 3.0, having this helps make you competitive. UofM should be no different from UTMem/K/Chat/Martin or AP/ET/MT/TSU, again, all entering classes are different, and trying to predict if you retaking Chemistry is a crap shoot compared to your future work in the other pre-reqs. For example, if you retake Chem and make a B, but continue to make B and C's in the other 50+ hrs, the Chem "B" isn't going to move your cumulative GPA.
Have you submitted the transcript from the community college? Although this will show up on your UofM transcript, they *may* take into consideration these were done while you were still in HS, which says a lot about your tenacity and ethic. As well, you did not mention your ACT. If its high upper 20-30 this might be considered. I had to take the GRE and did very well, which, in hind sight, believe it helped me slide into graduate school, versus my unimpressive GPA.
My recommendation, get into your freshman classes and try to do very well. Bring up that GPA, it can be done, I have experience myself. As well, ask your academic advisor, who should be in the School of Nursing or at least Sciences, as I believe they will recommend retaking Chemistry at UofM. While this will not erase the C, the School of Nursing may throw it out when they calculate your cohorts GPAs. The admissions committees try to be objective, they have to be, have a rather complicated formula to follow. I can imagine they "see through" some of the fluffy A's on many transcripts, after all, when the weeding starts, its the required pre-reqs that count. I know some schools use a pre-test called the HESI exam to discriminate between all those > 3.0 students. Some personal interview or written goal statements, depends if you are in a state school or private.
I wish you luck, keep your chin up and work hard. It will pay off!