Question

What is periscope? ​

Answer 1

Answer:

an apparatus consisting of a tube attached to a set of mirrors or prisms, by which an observer (typically in a submerged submarine or behind a high obstacle) can see things that are otherwise out of sight.

Answer 2

Answer:

device like a long tube, containing mirrors which allow you to see over the top of something, used especially in a submarine to see above the surface of the sea.

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