Agile Scrum - Testing Questions

1. What are the most important questions and provide answers as well if possible?
2. Agile tester realtime job from the day 1 of the project?
3. What documents he will receive and how will he work on them?
4. i have an interview for agile testing and i have not worked on them, so i just want to know the role of the Agile Tester compare to Waterfall Model tester?
i hope to receive the answers as fast as possible? as the interview in few days.