CSX Operations Research Intern interview questions

First round was a phone interview. They asked me basic HR questions and some questions about my projects which i wrote on my resume. After few days i got a mail from them stating that they would like to call me onsite for a 1:1 interview. They told me to bring a work sample along with me. On site i have met 3 to 4 people. Each one of them were managers. They told me about their role in the company and asked me few general hr questions and questions related to work sample i bought along. After two days they called me and informed that i was selected.