What is meant by the far point?

Name the part of the eye where the image is formed by the eye lens. What is the nature of the image formed? How is this image sent to the brain?

$(a)$ What will be the colour of the sky in the absence of an atmosphere?
$(b)$ Why are traffic light signals (or danger signals) of red colour?

Account for the following:
$(a)$ Part of the human eye that helps in changing the focal length of the eye lens.
$(b)$ The condition resulting due to the eye lens becoming cloudy.
$(c)$ The factors on which the colour of the scattered white light depends.
$(d)$ The range of vision of a normal eye.
$(e)$ The sky appears dark to the astronauts in space.

$A$ human eye can focus objects at different distances by adjusting the focal length of the eye lens. This is due to

When white light is incident on a blue pigment,which colors of light are reflected?