Give money bags a break! I’m sure its an amazing achievement to get to final round in itself! Look, one thing you have to understand is that they don’t give a damn what you studied! They did not put you through because they think you’re the next Warren Buffet! (Well, not yet anyway) They put you through because you meet their one-size-fits-all criteria.
At this stage they will be quizzing you on how well you know your degree/field of study.
If you’re studying classics they’ll ask you crap about the development of the Greek language or the significance of the Parthenon as a cultural anomaly.
Bottom line, know yourself, know your degree and catch up on your world business news, at least a months worth!
I hope this is marginally more helpful!
P.S Do you mind divulging your university/degree/year (you can pm me if you like) I’m just curious as to what academic background appeals to them