Answer:
A sphere has three, a circle has two, and a point has zero. What is it?
What is the center of gravity?
What can be seen but not touched?
A red house is made out of red bricks. A blue house is made out of blue bricks. What is a green house made out of?
It weighs next to nothing but no one can hold it for long. What is it?
I am owned by Old McDonald.