Can I charge my mid-2012 MBA using its USB 3.0 ports? My magsafe charger reached its peek. It doesn't work anymore. I'm looking for a way to charge it while I'm still waiting for my new one,  I was curious if I can charge it using the other ports it have.
You cannot charge it using its USB ports. In newer macs my understanding is that you can charge them with their USB C port. The only solution would be to order a new charger from Apple or pick one up from Best Buy. They’re about $100 USD or $125 CAD.