Amazon calculates a product’s star ratings based on a machine learned model instead of a raw data average. The model takes into account factors including the age of a rating, whether the ratings are from verified purchasers, and factors that establish reviewer trustworthiness.
THERE ARE NO ANSWERS! I bought this to help me learn Spanish (of course), but THERE ARE NO ANSWERS ANYWHERE IN THE BOOK!!! How can I tell if I am doing the work correctly??? If I knew that, I wouldn't need the book!!! I've considered asking friends who speak Spanish to check it, but that's a lot of work for them... This book is worthless.