Answer:
How many months of the year have 28 days?
Spies and detectives do this to phones and musical shoes make this sound.
How can a pants pocket be empty and still have something in it?
Casper was a friendly one and Demi Moore made a clay pot with one.
Once you know it exists, it no longer exists. What is it?
What is lighter than what it is made of?
Easy
Animal
Difficult
Food
Funny
Kids
Logic
What am I?