Answer:
What goes through a door but never goes in. And never comes out?
I am seen in the water. If seen in the sky, I am in the rainbow, a jay's feather, and lapis lazuli.
I am round as a bowl, deep as a tub, but all the world's water couldn't fill me up.
What is the thing that stays the same size, but the more it's used the more it decreases?
Until I am measured I am not known, Yet how you miss me when I have flown.
When is it bad luck to see a black cat?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?