1) Non-normal spaces cannot be metrizable. It is imply from statement that any metric space is normal (see [1]). Example of non-metrizable space: the topological vector space with the topology of pointwise convergence.
Particularly, If a space is not Hausdorff it's not a metric space. Example of non Hausdorff space is infinite with topology
2) For any metric space the collection of subsets form a basis for a topology on . It is obviously due to fact that an intersection of balls have another ball (see [2], first Lemma).
[1] https://math.stackexchange.com/questions/2872410/metric-space-is-normal-proof
[2] http://sites.millersville.edu/bikenaga/topology/notes/metric-spaces/metric-spaces.html
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