Look Ms, if you are 2nd and below it will impact you but the lower you are on the chain the worser it will affect you now can you stop asking a question which has been asked repeatedly for so many years.
The process and formula's become part of your muscle memory, you do not memorise.
The higher end questions examines you on your understanding of the topics.
What brent said was true, but unfortunately not anymore. If you want a higher chance, you'd need a minimum of around 86 (mid 80's) along with great reasons why it's best for you. A friend of mine got into Flexible with 86.45. To conclude, try to increase your possible ATAR by 3-5 more points...
Is there any method to be 100% sure which subjects I'm still enrolled in?
Like is going to Sydney Student -> My Studies -> Units of Study
enough to show which subjects I'm officially enrolled in?