That would be the city where the applicant will reside and apply for the AOS.

No unfortunately you must be a USC to do so.

You should have the paper receipt in hand for future reference.

Contact USCIS directly to inquire about final status of case.

Yes you may respond to the RFE by correcting the error.

Until the individual becomes a USC.

Yes this criminal record may impact a renewal or citizenship application.

Keep checking the online status to confirm the response has been received or contact USCIS to inquire. Otherwise yes, mail the documents at your...

Unclear why this information is required so many years after the fact. Was this specifically requested?

He would not have an alien number as he is a USC.