Answer:
1.refraction
2.reflection
3.plane mirror
4.lateral inversion
5.multiple images
6.parallel
7.concave mirror
8.diverging mirror
9.convex mirror
10.concave mirror
11.converging lens
12.diverging lens
13.microscopes
14.convex lenses
15.concave lenses
16.menicus lenses
17.eyes
18.eyelids
19.iris diaphragm
20.retina
xplanation:
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