It is very hard to go from arts into law. You are much better doing law at MQU or UNSW. Although if you are deadset on law at usyd I would transfer from law at mqu or unsw into usyd as many people that transfer from these unis get into usyd with 70-75wams.
85 is quite plausible but it'll depend on your performance and everyone elses because your school rank is not good and you are ranked well in your subjects.. 83-88~ (incredibly tough to guesstimate) sorry
93ish. Depends on the strength of your cohort this year as SR:205 will be unpredictable year on year and also since you are ranked well itll depend on your externals so 93 is a very bad guesstimate haha
90-98.5. Sorry for the large difference but its hard to estimate as you're ranked 1st in 3 of your subjects and you go to a poor school.. mostly it will depend on your own external marks :) goodluck mate