I got an interview offer for actuarial studies as well!
I have a couple of questions about the interview if that's alright!
Congratulations!! And absolutely, happy to help

1. Definitely nothing that specific, the "What do you know about us?" question could pop up but nothing more. And to be honest I didn't even get that. My advice would be to know a bit about all your sponsors (main areas of work, I guess), to show your interest in the industry, and so you can chat to your panel with a bit of knowledge of their background.
2. I think this is a great question on so many levels, because even
what you pick to talk about tells them a lot about you. There's no right or wrong, though I wouldn't go super formal with it. Like, it feels unnatural to have someone ask about you and you go on with specific examples of leadership skills. Go for broad statements with limited specific examples. EG, "Sure! So I guess the big thing about me is that I hate doing nothing, I always like to be busy, so I tend to cram my days pretty full. In the HSC I had a job, volunteered, all that sort of stuff. I've been told I work too much (insert casual laugh), um... I'm super into technology! Bit of a gadget freak and was super into the parts of my Physics course on how technology works. For this reason, Electrical Engineering seemed like a perfect fit, that's why I'm here I guess!"
3. About 20 minutes? Definitely don't need to wait for your group

4. You (and many others) have a slightly incorrect idea of these interviews - This isn't testing your intricate knowledge of the content of a course you haven't done yet, nor your knowledge of sponsors which you've to this point had nothing to do with. They want to know about you, why you want to work in your industry, and what you'd contribute to their companies as an employee. Any questions they ask that are specific will purely be to gauge your interest in the subject matter. "Oh you are interested in the stock market! Do you mainly watch the ASX or do you keep up with international exchanges too?"
5. You can, but you don't
need to unless you get a conditional scholarship offer. At that point, move Coop first (if you want to accept) and keep your fingers crossed for the ATAR
