Hope this answers your question.
Previewing is a part of active reading because you’re taking the time and dedication out of your day to understand what you’re reading. Previewing is an effective reading strategy because when you actually get into reading the book you’ll know kind of what you’re reading and the purpose of the book. This can help make more accurate infers. Not to mention reading books make you smarter. It’s a win win in my book!
Once again, I hope I could help.