Flux density versus wavelength for an example SDSS spectrum (black) to show the location of our discriminating features along with their respective wavelength ranges (Table 2). The central wavelengths of the targeted features are indicated by red dashed lines, and the shaded gray areas represent the ranges for the EW calculation of each spectral feature. The purple shaded areas n the either side of each band show the areas used to estimate the continuum for the liner fit.