It should be hyphenated if it's being used as an adjective.
No, a hyphen is not needed.
The correct spelling of hyphen is nephyh
No.
No, faux pas doesn't require a hyphen.
Yes
Yes
No.
I think it would be preferable in most cases to write 1880's. I would not spell it out.
Ideally, yes
No it doesn't require to be hyphenated.
These are two words. There is no hyphen in the concept. In charge means to have leadership in English, so there is no hyphen to connect the two.
Yes. "Hard-working" is a compound adjective, and therefore requires a hyphen between the two words. It is also correct to omit the hyphen and use the single word, "hardworking."