Yes. You can take notes into the exam, and you don't have to clear your CAS's memory. You can write stuff on your hand if you feel like it, there won't be any issue with labelled keys.
That looks a bit sus, even though you can take in notes. In fact, probably not allowed to be honest.
A lot of people don't know this, and I only learned it today, but your VCAA Exam supervisors write down little incident reports about the littlest thing. They don't exactly tell you that they are doing it, but they just do it and I think its filled at the end of the Exam. This is then enclosed in the pink bag with everyone's exams and is then collected. Incident Reports may be made for things such as constantly putting hands in pockets. Another example is giving a phone up to a supervisor when the main supervisor is giving instructions just before Reading Time commences (Even though they ask then, phones and other electronic devices should be handed up before you enter the Exam room, so before you sit down).
You don't get into trouble (Well you could), but its just so that VCAA knows exactly what is happening. However, apparently you do get told at the END of YOUR EXAM PERIOD, so after your last Exam.
So don't do anything dodgy, otherwise another incident report will be made.