Counting my BOBs

Hi this is Benofschool and this is my BOB for the Combinatorics Unit. The easiest part of this subject is the simplifying factorials and the Binomial Theorem. I understood those parts of the unit pretty quickly but the part that I am having the most difficulty are the Word Problems like how many ways can these books be sorted. Other examples would be the worksheet that was given to us when Mr.K had to leave because he was late for a meeting. Those question I am having difficulty on. I can't seem to find out how to solve them. I don't understand which formula to use nor do I know what the questions are asking. I might seem angry but I'm not see? :) I'm just a bit stressed out. I'll pull through...