What Am I Riddles

Question: I have eight to spare and am covered with hair.

What am I?

Question: I can hurt you unbearably and can't be touched. What am I?

Question: Without fingers, I point,
without arms, I strike,
without feet, I run.

What am I?

Question: Round like a dishpan and smaller than a bathtub.But the ocean can't fill it.What is it?

Question: When you do not know what I am, then I am something. But when you know what I am, then I am nothing. What am I?