Question: Tuppence seemed to shake herself free of it with an effort, as she said: "We couldn't do that, could we, Tommy?" But to her surprise, her companion did not back her up.
Her companions backed her up in her efforts.

Answer: no

Question: (The same is true for another of Vietnam's most famous Eddie Adams' photo of the gun-to-temple execution of a Viet Cong.)
It is not true for another of Vietnams' most famous Eddie Adams' photo.

Answer: no

Question: It's all shiny silver or something."
It is shiny silver or something similar in material.

Answer:
it is not possible to tell