Goodreads is a website where users can rate books they’ve read and share their ratings with friends. Books are rated on a scale from 1 to 5 stars, with larger numbers representing better books. A random selection of books has overall ratings that are bell-shaped with mean 3.9 and standard deviation 0.35. A new, popular book has an average rating of 4.5 on Goodreads. Determine the z-score for this book.