[Thm C3]: Compact then Totally Boudned

設 $K\subseteq(M,d)$ 是 compact set 則 $K$ 是 totally bdd

[Thm S3]: Sequentially Compact then Totally Boudned

設 $S\subseteq(M,d)$ 是 sequentially compact 則 $S$ 是 totally bdd