Easy Riddles and Answers

Question: How can you add 9 to become 6? (No subtracting).

Question: What goes up and down but never moves?

Question: I am important at the most dangerous times. I can not be seen, heard, or smelled. If you use me too much you would fatally die. What am I?

Question: When you close it, you see mysterious and funny looking images. But if you open it, the mysterious images are gone. What Am I?

Question: What key is playful?