(i) The rainbow is formed only if the atmosphere contain large number of tiny droplets of water suspended in the air. As moon has neither atmosphere nor water therefore no rainbow is formed.
(ii) The ability of the eye to focus the distant objects as well as the nearby objects on the retina by changing the focal length or converging power of lens is called accommodation.
Ciliary muscles can modify or change the curvature of the eye lens change the focal length of the eye lens.