I'll assume that its about a 5 - 6 line answer? Meaning about 5 marks? Correct me if I'm wrong, as I don't have the paper infront of me.
I hated this question as well, I always used more space that what was available. You can write extra off the lines if you want, they still mark it, but just don't go over too much. Another 3 or so lines maximum (i think).
From memory, cause I've forgotten where I've put my notes.
The major things to talk about will be:
- Movement west to east
- The three oldest regions in Australia
- The timeframe
- What tectonic processes
I think you know what to talk about. You just need to learn which bits are important and which bits aren't. You'll be a master of it by the end of the HSC