Funny Riddles

Question: Light hides me and darkness kills me.

What am I?

Question: Weight in my stomach,trees on my back,nails in my ribs,it's feet I lack.What am I?

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?

Question: What is a word made up of 4 letters, yet is also made up of 3. Sometimes is written with 9 letters, and then with 4. Rarely consists of 6, and never is written with 5.

Question: How many animals of each kind did Moses bring on the ark?