AE: The algorithm terminates when the centroids stabilize or when a specified number of iterations are completed.
B: A measure of how well the centroids represent the members of their clusters is the residual sum of squares or RSS, the squared distance of each vector from its centroid summed over all vectors. RSS is the objective function and our goal is to minimize it.
References:
https://docs.microsoft.com/en-us/azure/machine-learning/studio-module-reference/k-means- clustering
https://nlp.stanford.edu/IR-book/html/htmledition/k-means-1.html