Can't think of much to add to what VFE says. Yes, some questions are badly worded, not on the syllabus, and so on. Hopefully you'll see them in the feedback and be prepared for some of them, but you might still get a couple that can't be answered.
The pass mark is 75%. Some people make the mistake of thinking that when they can get 75% on the feedback papers, they're ready. But it doesn't work like that, because there will be a few questions which you have absolutely no chance of answering.
Learn the syllabus, and learn it well. You should be able to get 90% of the "good" questions right. If you can do that, you'll get 76% on the exam even if 15% of the questions are un-answerable. That should be enough for even the most off-syllabus badly-worded exam.
(The only exception is Air Law. I don't believe anyone knows 90% of the Air Law syllabus.)
FFF
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