Question

A tall device which contains plane mirrors can be used to see over the heads of crowd (ad in a football match). a) what is the name of this device?
b) How many plane mirrors does this device it use?
c)on what principle does this device work​

Answer 1

Answer:

(b) is right answer you like me

Answer 2

A) The device is periscope

B) It has 2 mirrors

C)A periscope works on the basis of laws of reflection of light.

Hope this answer helps you