My suggestion is if this book is not going to be examined then the answer to your mind-probing question will be found in another book.
But if the book is to be studied for school, then the question you asked will not be examined, obviously, because the answer doesn't exist. If on the very rare occassion you went 'blind' when searching and passed over it, then you must determine if this is probable and decide how much time you will spend searching for it.
You must dominate the book, take control. Make a decision to whether you will spend another 20min pass on the book (i.e activation section)
