We've got your back. With the Tough-O-Meter, you'll know whether to bring extra layers or Swiss army knives as you summit the literary mountain. (10 = Toughest)
(2) Sea Level
Despite a few technical terms, reading this book is not too strenuous. The terms are simple, the action well-explained, there's no gore, and it's short. In other words, this book is perfect for an afternoon reading stroll.