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## Chapter 4 Exercise

1. Empty 2. Solution: False. Consider $1=(z^m+1)+(-z^m)\notin \{0\}\cup\{p\in\ca P(\mb F):\deg p=m\}$. Note that $(z^m+1)\in \{0\}\cup\{p\in\ca P(\mb F):\deg p=m\}$and$-z^m\in \{0\}\cup\{p\in\ca P(\mb F):\deg p=m\},$it follows that $\{0\}\cup\{p\in\ca P(\mb F):\deg p=m\}$ is not…