My school did the Independent Trial. Don't have it though, but if you end up somehow getting it, it's a really hard paper and I'd say anything over 75% is a good mark.
Umm...maybe you are confused? Are you doing the SC next yr and asking for a practice paper??? If so, the 2011 SC hasn't been done yet, not even the teachers have seen the paper...
The only teachers who have seen the papers at this stage are the ones who wrote it and they have signed a confidentiality agreement that says they can't discuss the contents with anyone who isn't on their committee or the BOS itself.
Like the HSC students see the exams before their teachers.