par(mfrow=c(3, 3))
hist(as.numeric(data_cleaned$Cl.thickness))
hist(as.numeric(data_cleaned$Cell.size))
hist(as.numeric(data_cleaned$Cell.shape))
hist(as.numeric(data_cleaned$Marg.adhesion))
hist(as.numeric(data_cleaned$Epith.c.size))
hist(as.numeric(data_cleaned$Bare.nuclei))
hist(as.numeric(data_cleaned$Bl.cromatin))
hist(as.numeric(data_cleaned$Normal.nucleoli))
hist(as.numeric(data_cleaned$Mitoses))