I don't think so. You do three separate internships during the 4 year degree. With each, you work for a different company and they each last 1 semester. So the internships occur during uni semesters, not during summer holidays - but im sure they have options for that if you're keen! :)
I don't thin that's true. The published ATAR cut off is over 96. You need that to make the application process. Once you've made it in, they decide based on personality, achievements and co-circular activities. You're ATAR may come into consideration, but i doubt it!