Sales and Trading summer analyst

I first applied through campus career website. After about 2 weeks or so, I received a email to schedule for a phone interview. Apparently they only have time slots for the next day at 10 am, so I was not really given much of a choice. On the next day, the interviewer called on time. The interview lasted only 15 mins. All of the questions are behavior questions, including: Walk me through your resume. Why trading? Why change of major/career path (I was doing environmental science)? They also asked about a question regarding one of the class I have taken because I listed it on my resume. Finally they asked me if I do any trading with mock accounts and etc.