When red and green light overlap,what color does that region appear?

Which optical phenomenon is responsible for the formation of a rainbow?

The clear sky appears blue because

What is meant by scattering of light? Mention the factor on which it depends. Explain why the colour of the clear sky is blue? An astronaut in space finds the sky to be dark. Explain the reason for this observation.

Every colour travels with the same speed in a transparent medium.

What is the central aperture of the eye located behind the cornea called?