1. You have strong numbers and a solid resume, but as an Asian engineer you're still traditional ('turquoise' is a variation of blue, not a different color altogether). As such, you have enough of a shot that they're all worth applying to, so long as you know they're going to be stretches. You need strong applications as well as a bit of luck.
2. Age in your case won't be an issue. Don't worry about it.
3. Not sure what you mean. The whole sustainability/green thing is too new at this point for any school to be better or worse than others, and as such every b-school is figuring it out as they go.
4. It's about their ability to comment on your caliber and potential as a future manager (i.e. your interpersonal/leadership skills), and not what school they went to. There's tons of people who could get rec letters from alums -- and adcoms don't care. Again, what matters is how well the recs know you and their ability to articulate your potential to be a great boss to work for someday.
5. Yes. At any b-school, a significant chunk of the class went to undergrad there as well. No matter what adcoms say publicly, it does help. I don't have data to back this up, but my guess is that alums who have multiple degrees from the same school are more likely to be larger donors to the university as a whole over time than alums who only had one degree from the school (i.e. the fact that they want to "come back" for another degree signals someone who is very loyal to the school and will likely donate more money longer term).
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