ch2 issues and questions

[cpengb]

I'm a university faculty who intends to use the book in my courses. I worked through chapter 2 and got questions in sections 2.2, 2.3, 2.5, 2.7 - 2.9. Some may be typos, but some may be mistakes related to exercises and their automatic responses. Because of the number of issues, I put those in a google doc with descriptions and screenshots: https://docs.google.com/document/d/1IKrHVuozfHn0tQd-9wDW1c7YxirAQd17hp2FpK7Pn-4/edit?usp=sharing
I contacted one of the authors and was directed to post it here. Thanks in advance for your help!