Question 9: Sometimes gasses, dust, ect. mess around with light waves.
Edit: Oh, darn, didn't realize there was a page two. /sigh. I guess I'll go into more detail. When it's on the horizion, it's actually farther away then it is when it's in the sky, so more light has to pass through the atmosphere. Only stronger lights waves make it through, red, yellow, and orange. Shorter ones(blue, green, purple) don't make it all the way through, so it doesn't appear white(when all of them make it through).