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Answer:
See the explanation.
Explanation:
Q9. Irregular reflection happens when a set of parallel beams are reflected from non-smooth surface which results in non-parallel reflected beams.
Q10.
i) Periscope
ii) There are different types of periscopes but the main characteristic of this instrument is observation over the obstacles or in general objects that are not in the line-of-sight. Basic Periscope uses parallel angled mirrors to project objects that are above the surface in submarines.