用R来总结集群中的变量变化(k-means)。

I have a df that I got after implementing k-means clustering on my original dataset. I have 4 different clusters here and what I would like to know is how much is the variation of the 4 variables (V1 to V4) in each cluster. In other words, what variation in those 4 variables is causing the clusters being separated. I have a df that I got after implementing k-mea