If you trying to learn things from this book, well you aren't going to be learning a lot from it. Because this is basically how most of the book is: "oh you didn't get why you got this answer wrong and need more help on the questions? well do it again and I will not even put any pages related to these questions that can help you understand them." and it gets very frustrating, its like teaching a child how to ride a bike except you don't actually help him, you just watch him attempt to try and ride the bike and then watch him fall off of it for 20 minutes.