Synthesized answer
The provided passages do not explicitly list any unanswered questions. [Passage 1] is a title and author citation for the book "Software Requirements (3rd Edition)". Therefore, based solely on the information given, it is not possible to identify what questions remain unanswered within the book.
Synthesized from the book passages below. Chat with the book on Feynman for follow-up.
From the book
Title: Software Requirements (3rd Edition) (Developer Best Practices) by Karl Eugene Wiegers, Joy Beatty