My favourite color is blue.
Oh, I love blue. Isn't it a primary color?
Oh yes it is
The sky is very blue where I live. Do you know why?
I do not now can you tell me
I just found out so now I can answer the kids when they ask me. It's called Rayleigh scattering.
What caused it?
It's a optical effect that makes the daylight sky and the sea appear blue. It's different for eye color and things far away.