The book covers some pretty basic, but required information. Math, grammar, reading comprehension, and test taking skills. This is a study book, you need to practice and think while going through it. If you just read through it as fast as possible you won't get much from it. Hopefully these sections are test prep, not learning. Your ability to arrive on scene and assess a situation and then later write your reports can make or break cases, careers, and lives.
There are topics specific to policing, but it's focused on generalized application tests and that's it. This is test prep, it does what it needs to for the exams, starts getting your mind in the right place. If you're putting forth effort to study and prepare you're on the right track. I'd highly recommend some other basic reading on what it takes to be a police officer. The more you know about what you're getting into the better you will do on all aspects of your selection process and then career.