Good Riddles

Question: What demands an answer, but asks no question?

Question: What is one in every doll, in every doll, in every doll?

Question: What is it that no man wants, but no man wants to lose?

Question: I'm heavy but not backwards.

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.