Auto Mechanics to Quantum Mechanics

I have a schtick I do at the beginning of each class where I allow the students to ask me any question, auto mechanics to quantum mechanics, I tell them that any question at all will be entertained. I had some former students who come here to play ask me if I could bring it back and so every couple of months, I solicit questions. So, if there was ever anything you always wanted to know, a question that has been nagging at you, or a real stumper you haven't been able to figure out, fire away and I'll answer as many as I can in the posts this coming week. Any questions?