No difficult questions. Just give simple examples from your experience (e.g data analysis, difficult situation, how you work around complex task, etc.). Its nice that during the interview with the manager you can ask questions. Take advantage of that as you can understand quite a lot about the position and the person himself/herself. I might have have gone a bit too far with my questions which by no means i regret. Its important that you understand what you are about to get into and make decision how that fits your career expectations. HR contacts in my case were a train wrack, had to send them 2 remainders to confirm the date of the interview. She than cancelled 5 minutes before the interview and when we finally got to talk she acted disengage. No regrets only good experience.