Yes.

Yes.

离婚证都是中文的

-Ask your friend to translate it into English, then go to the Notary Public to notarize your friend's signature. Your friend also needs to provide the statement addressing that he/she knows both English and Chinese well and the translation is accurate.

See:

https://www.uscis.gov/forms/forms-and-fees/general-tips-assembling-applications-mailing

http://www.immihelp.com/immigration/document-english-translation.html