Get the data on fragments of glass collected in forensic work from the book website. Estimate the density of the ?rst variable (refractive in- dex) using a histogram and use a kernel density estimator. Use cross- validation to choose the amount of smoothing. Experiment with di?erent binwidths and bandwidths. Comment on the similarities and di?erences. Construct 95 percent con?dence bands for your estimators.