Answer:
I am lighter than air, but a hundred people cannot lift me. Careful, I am fragile. 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.
My rings are not worth much, but they do tell my age. What am I?
Lives in winter, dies in summer, and grows with its roots upward. What is it?
I get dirty when wiping things clean. What am I?
What do you purposefully put lots of in and on your body, but run away from when you encounter it outside?