You WANT your teacher to crucify you in SACs. As long as everyone in your school is marked the same way, you want to be drilled into the ground in SACs - too many people get an inflated sense of their own performance in SACs because they keep getting 90% or higher, and they just WON'T get that in the exam (I'm speaking in generalisation, here). Look at the statistics for exam raw scores; if anything, ask your teacher to find *more* problems in your work!
Also, statistically it works slightly in your school's favour with the moderation process if the teachers report lower SAC marks than the average exam mark ends up being.
Okay, as for the questions:
1. An absence of examples would not necessarily lose you marks if the question did not ask for them... but considering your definitions are probably around one mark each, what extra info are you going to include to get the second? Merely saying the same info with more words isn't adding any content. Use examples. Wherever possible.
2. Same. Won't necessarily lose you marks unless the question asks for them, but why take the risk of leaving them out? The best students will generally all have them in their answers.
3. In my personal opinion you don't need ss7 and 24 for Roach because the whole point is that it's a structural protection rather than an implied right - meaning it is taken from the overall structure of the Constitution and the principles established in it, and not one or two individual sections. I recommend my students follow this by saying "in particular, ss7 and 24" just to be safe, but I personally would not dock you for not including them. You have to realise that some marking points are always going to be subjective, though.
(Just re s109, don't forget to finish that sentence by saying "...invalid *to the extent of the inconsistency*"!!

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