Radius of a cluster - K-means

Hello

I am doing a project on clustering for my engineering course. I need to apply K-means clustering algorithm provided by Weka on the WDBC (Wisconsin Breast Cancer Database). But the SimpleKMeans algorithm under the Clusterer tab is disabled. I want to know how to convert the existing dataset to numerical so that I can apply K-means over it.

Also, I would like to know how to calculate the radius of each cluster once the clustering results are output by the K-means algorithm. I also need to find out the distance of each object from the centroid of the cluster to which it belongs.

Thanks

Shambhavi Joshi