1. Redo the example for spectral clustering by changing the "nn=10" to "nn=20" in line 4 of the R code and discuss the changes. a. plot the last 10 eigenvalues as we did in the class. How many values close to 0 this time? Discuss why. b. plot the final clustering results. Discuss the changes and the possible reason.Source: https://rpubs . comurakawa/spectral-clustering # another example can be found here: http://www.di . fc . ul. pt/~jpn/r/spectralclustering/spectralclustering. html 3 4 mutual_knn_graph