This is the PADI Scuba Diving Knowledge Workbook - 70214 Features: This book is ideal to anyone with a desire to learn more about the academics of diving The Diving Knowledge Workbook is a self study guide to help evaluate and enhance your understanding of the most important aspects of recreational diving: Physics Decompression Theory The Aquatic Environment Equipment Physiology The Recreational Dive Planner Keep learning and stay up to date on all the latest knowledge with PADI&';s Scuba Diving Knowledge Workbook.