Transmission of sound and images

Hello to everyone again!

I am having a few more question today and am hoping very much that someone might be able to answer one or all of them :-).

- Which are the technological and/or physical means of transmitting sound and image to a human being?

- Is it possible to verify afterwards that a human being had been exposed to radiation and for how long the exposure had taken place?

- Can satellite communication be traced back?

Thank you again in advance. Stay healthy.

Phoebe