3. Conduct the PCA analysis yourself to replicate the results shown above (include all PCs, not just the first 6). Then, also perform data normalization and conduct the PCA again. Now, provide the eigenvectors and eigenvalues for all the PCs (output should look similar to the one above, but include all PCs). Comment on effect of normalization. How many principal components should be retained after analysis if 90% of the total variability is to be accounted for