viii Features of the Textbook Features are student-focused learning tools designed to help you get the most out of your studies. This visual guide highlights the features designed for the textbook. Learning Objectives clearly identify the knowledge and skills to be obtained when the chapter is completed. Technical Terms list the key terms to be learned in the chapter. G-W Learning Companion Website Activity Icon identifies related content available on the G-W Learning companion website. Safety Concerns are presented in bold red type throughout the book to make you aware of things that could potentially endanger the safety of you or people around you. Warnings alert you to potentially dangerous materials and practices.