Connected complete metric spaces with more than one point.

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Does every connected complete metric space with more than one point have infinitely many closed balls? And is any closed ball in a connected complete metric space connected?

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  1. Yes. Take distinct points $a,b\in X$. For $0<r<d_X(a,b)$ there is a point $c\in X$ such that $d(a,c)=r$; indeed, otherwise $X$ would be the union of disjoint open sets $\{x:d(a,x)<r\}$ and $\{x:d(a,x)> r\}$. Therefore, all closed balls $\{x:d(a,x)\le r\}$, $0<r<d_X(a,b)$ are distinct sets.

  2. No. An example was given in comments. For another example, remove the open rectangle $(-10,10)\times (0,1)$ from $\mathbb R^2$; keep the metric the same. The closed ball of radius $2$ centered at $(0,0)$ is not connected.

By the way, completeness was not used in the proof of 1.