Good Riddles

Question: What asks but never answers?

Question: To many, I am life's source. I am also its most valuable resource. I create and burn my own precious element, and my destruction will be my punishment. What am I?

Question: I have 6 faces and 21 eyes, but can't see a thing. What am I?

Question: What cannot be seen or felt, but can only be broken by voice?

Question: You build a house and all 4 walls are facing south. Where did you build the house?