Concerning chapter 20 Incomplete records BPP revision kit

Questions in this chapter require to use accounting equation and mark up and margin which were covered by the lectures and notes however there are terms which are unfamiliar like bank and cash summary in question 20.12 and i have no idea how to deal with question 20.4 and 20.5 . overall i have been able to work only few questions in this section. Can you take a look and tell if i have missed any material in order to answer the questions.