Answer:
The most accurate option is hopefully, but we do not have enough context and however could also work.
The author explicitly says that spirit can be found in the voice of a character.
Explicitly means directly - so it means that the author didn't hide the fact that he knew what could be found in the voice.
Here is what he says:
<em>That is wholly appropriate, for in the breath—the voice—of a character lies its essential spirit.</em>
So the correct answer is definitely spirit.
False. The contents of any letter is not also on the envelope. Only things on the envelope are the address, name, and maybe a company name and logo.