I stumbled upon this in a park near Philadelphia, and snapped some photos of it and thought I'd post it as a CSI examination.
1)Are these dents from a Firearm?
2)If so, what caused them?
3)If it's not a firearm that caused the dents, what could have?
4)Would a basketball backboard stop a firearm from penetrating it?
I have more pictures, but I think this first one gives you soemething to discuss first.
Any questions you want to ask?