This book was a very big disappointment. There are errors all over the book. So if you're trying to use this book, to study for the test, I suggest that you do not. You'll spend most of the time, wondering if the strategies or answers are even correct. There are errors on pg 19,example 2, pg 29, example two, pg 38 in the box of converting units, pg 53, example two, on page 85, example two, and on page 119 when they explain cosine. These are the errors that I found. Who knows, there may be more in it. So please don't make the mistake that I made by purchasing this book.