Copyright Goodheart-Willcox Co., Inc. May not be reproduced or posted to a publicly accessible website. iv Features of the Textbook Learning Objectives clearly identify the knowledge and skills to be obtained when the unit is completed. Warnings alert students of potentially dangerous situations and remind them of best practices in safety. Note boxes provide additional information related to the topic being discussed and often prompt further self-guided research. Step-by-Step Procedures appear throughout the textbook to provide clear instructions for hands-on activities. Students can refer back to these procedures easily. Key Terms list the technical terms to be learned in the unit. Review this list after completing the unit to be sure you know the definition of each term.