Answer:
I am black when you buy me, red when you use me. When I turn white, you know it's time to throw me away. What am I?
As a state in the USA, I am round on both sides and high in the middle. What am I?
I am two-faced but bear only one. I have no legs but travel widely. Men spill much blood over me. Kings leave their imprint on me. I have greatest power when given away yet lust for me keeps me locked away.
You can catch me but cannot throw me. What am I?
I'm not a bird, but I can fly through the sky. I'm not a river, but I'm full of water. What am I?
Almost everyone needs it, asks for it, gives it. But almost nobody takes it.