I ask because I have 12 units, my extra 2 units are chemistry - because I've always known it wasn't my strong point. Will the universities I apply to ever see my chemistry mark if the other 10 units are used to calculate my UAI?
Well all they care about is your UAI which is derived off your HSC marks so it's sort of irrelevant. Seeing as the UAI takes your 10 best units they wouldn't even bother looking at the 2 left out.
They get both, but like said above, does it matter for you? Two reasons why it could matter:
1. You're hoping to get Academic Advantage, or whatever the system is at your prospective uni where you get 'bonus' points based on your HSC performance,
2. if the subjects/degree you're looking at doing at uni have HSC subject requirements.