UPS Analyst, IT interview questions

only had 1 HR interview then was pushed to a panel interview with many (3+) questions about large problem solving concepts. Was not warned about there being a case study or that the next round was a panel and not an individual. I got the offer without ever discussing salary and it was lower than the first job offer I got after graduating, with 5 years of experience and a masters since that time. Frustratingly hard interview for such a low paid position.