From this information, your performance seems to be consistent with an ATAR between 86 and 88-89.
Mathematics Advanced and Music 1 appear to be your best-performing subjects, and are therefore likely to make a positive contribution to your ATAR.
The same can be suggested, although perhaps to a slightly lesser extent, about your performance in Chemistry and Mathematics Extension 1. This means that both subjects are also likely to make a positive contribution to your ATAR, although it may not be as significant as that of Mathematics Advanced and Music 1.
On the other hand, Biology and English Standard appear to be your lowest-performing subjects. In this case, I am referring to your performance in these subjects compared to that in your other subjects, as opposed to your actual performance in each of them.
This brings us to two important elements that are relevant to you:
- Your HSC exams contribute the remaining 50% of your overall HSC marks for your subjects. This means that your performance in your HSC exams will be important in determining whether you end up achieving an ATAR in this range, or whether it ends up being different (hopefully higher, depending on how well you actually performed).
- Since you are ranked first in most of your subjects, you could technically achieve an ATAR that significantly exceeds this estimate, thanks to the moderation process. Assuming that you achieve the highest HSC exam marks in your cohort in these subjects, your Assessment Marks (internal marks) will be made equal to your own Examination Marks (external marks). In other words, your Examination Marks would become your overall HSC marks. From this point, the higher your HSC exam marks, the higher your ATAR (hopefully you did well in your HSC exams!).
I hope this helps!