Books of prime entry and petty cash

Hi, I’m studying by myself following the lectures and the notes; at the end of each chapter I do the relative test. I think there is a problem regarding chapter 10 which in the notes is about the use of computers in accounting while the test is about the books of prime entry. I can’t find this topic anywhere in the lectures or in the notes and doing the bpp revision kit I noticed that there are several questions about petty cash. Has this topic been removed from the syllabus? Why is it not explained anywhere?
Thanks