State any five precautions that are needed to take care of our eyes.

Explain how optical and non-optical aids help visually challenged persons to develop their skills to a higher level.

Solve the puzzle with the help of given clues.

Across:

$1$. far-sightedness

$2$. an opening through which light enters the eye.

$3$. the white of the eye.

$4$. eye lens becomes opaque due to development of membrane over it.

$5$. sends the electrical signal to the brain

6. dark-coloured muscular diaphragm

Down:

$1$. Light sensitive cells

$2$. defect corrected by an appropriate concave lens

$3$. the screen of the eye

$4$. system which has $63$ dot patterns

$5$. sensory nerve cell which gets activated only in bright light

$6$. focusses the light rays on the retina