Answer:
I cost no money to use, or conscious effort to take part of. And as far as you can see, there is nothing to me. But without me, you are dead.
If eleven plus two equals one, what is nine plus five equal to?
What kind of running means walking?
My first keeps time, my second spends time, my whole tells time.
Break it and it is better, immediately set and harder to break again.
When is it bad luck to see a black cat?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?