Short Riddles and Answers

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

Question: I can be cracked, I can be made. I can be told, I can be played.

What am I?

Question: What is black when you buy it, red when you use it, and gray when you throw it away?

Question: If a white house is white and a yellow house is yellow, what color is a green house?

Question: Take my first and make it my last, now I happened in the past.

What am I?