After reading/reviewing chapters 9 and 10, post what you think is THE most impor

After reading/reviewing chapters 9 and 10, post what you think is THE most important thing (MIT) presented in either of those chapters. Only ONE important thing from ONE of the chapters is required. Be sure to include which chapter and page number (or area) of where we can find that topic.
As usual, these chapters are very involved, so there is no “right or wrong” answer. But – you must justify “why” you think your chosen topic is important. Posts should be at least five sentences long to count for an extra credit point.
chapter 9 part 1 https://www.screencast.com/t/z1Gs5e3hSdd
chapter 9 part 2 https://www.screencast.com/t/vykDiqS6bml
chapter 10 part 1 https://www.screencast.com/t/9oywuRthhI2
chapter 10 part 2 https://www.screencast.com/t/EkoVgOPLCP