To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyzes reviews to verify trustworthiness.
Needed this text for a teacher course and didn't want to pay way over $100.00 for it. It came within a few days and it is exactly what the Used Book seller it would be ...used but in very good condition.