Perhaps the most useless book I have purchased in recent years. Incredible sloppiness. It does not include contents or proper annotations and bibliography (the poor author found the answers, no one knows...). The worst part: the answers have many mistakes (some are completely wrong or off-topic) and omissions. The author could have grouped them by subject and semester (there is a study guide for this) instead of having them scattered. This way, studying would be much easier.
My advice: do not buy the book. Gather the questions based on the study guide and ask the professors.
The book will confuse you even more.