Stone tools are pretty much eternal. So are the foundations of stone structures. Bones are actually very impermanent and go away rapidly in acidic soils.
Our current culture will actually leave less behind than many ancient civilizations. High-strength concrete turns to dust in a few centuries...
Unless she obviously was not 19 I wouldn't say you're a bad person. It's not always obvious.
How much trouble, if any, you're in depends on your state. I know that in my current state of Louisiana ignorance is an acceptable defense. Look up your state laws!
I think the question is why does the world work the way it does.
I don't know. Most of physics can be traced back to very basic concepts. Energy is conserved because 1=1. 1 is not equal to 2.
Why does 1=1? Is there even any meaning in asking such a question?
Does the belief system you're...