Answer:
Gumby and yoga instructors have this in common.
What was the first man made invention that could see through a wall?
A standard dimension for sandwiches and rulers
What travels around the world without leaving the corner?
It is in every mountain, it's not in any hill, it's not in all the world, and yet it's in the mill.
I am a room that has a roof but no walls. What am I?
Easy
Animal
Difficult
Food
Funny
Kids
Logic
What am I?