Answer:
What is bought by the yard by is worn by the foot?
What instrument can make any sound and be heart, but not touched or seen?
I am free for the taking. Through all of your life, though given but once at birth. I am less than nothing in weight, but will fell the strongest of you if held.
By Moon or by Sun, I shall be found. Yet I am undone, if there's no light around.
This is in a realm of true and in a realm false, but you experience me as you turn and toss.
What did the piece of wood say when he saw the screwdriver and screws approaching?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?