the only thing you can really do is constantly do practice tests I know it sounds cliche but it works really well. I did my HSC for Maths last year and for task one I got 55% and I ended up getting a band 6.
im about halfway through the 3U course and it is a lot harder. I can confidently say i'll get a band six in 2U but I don't know if i'll get a seventy in 3U.
I'm pretty certain that there was religion about ever since the dawn of man. Most monotheistic religions believe that Adam was the first man created by god and did meet him, so he therefore would have preached to his children that there is a god, the things god likes, the things he doesn't like...