I'd say that Rutgers is a possible with a 600 GMAT. It looks like their average is about 640, so it's possible to get in with a 600. That said, it won't be easy, and you'll want to compensate for the lower GMAT score with other strengths: really demonstrate your professional leadership, show your extracurricular and community leadership (although seems like you were most active in college and not so much thereafter?), and make sure to have a strong career narrative. You already have a Masters degree and an MBA, so you have to be careful not to come across as a "degree collector"...
I'm not sure that top 40 is very realistic with a 600 GMAT - I would put one or two on your list, but might also have some tier 2 programs in there. You could look at schools in the range of Iowa State (average GMAT is 615), Syracuse, etc.
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