Chapter 9 should be formatted the same as the other chapters in the text. The layout is not consistant from chapter to chapter (Introduction (should be a brief one); Learning objectives; Content; Test Your Knowledge). Learning objectives should be written to be in a consistant format, using appropriate descriptors (Unit 2: Relevant Experiments: State and Explain is redundant, choose one. Unit 3: How do you measure "See" the effects? of this learning outcome. Test your knowledge sections are not consistant throughout each section/chapter and is in various formats. Consistency in placement and format is needed.