Think of a group interview as an opportunity to show how you can work in a team. You may think you need to be adversarial (after all, you're all trying to get the same spot) but showing you can work as a member of a group is more important. Build your own answers off of others. For example, "I thought Joe's idea for increasing widget sales in the northwest region was a good one and reminded me a lot my senior Finance project. I think we can beat sales expectations by ...."
Regarding the laptop, I'm guessing vlookups, pivot tables, pivot charts, maybe some Access or basic SQL queries.