Seriously, in less time than it takes to post a question here, you can get multiple explanations to most of the questions in the blue book. Just type the first few words of the question into the search bar. You will be amazed how quickly google recognizes the problem and points you to a variety of explanations for you to choose from. Try it yourself and see…
(I put this as its own thread – there are probably 10 threads each week that this would apply to.)