7. One way to analyze E MR is to pass the radiation through a prism or a diffraction grating. This causes the radiation to separate into its component wavelengths, producing a spectrum. Depending upon the source, three types of spectra can be observed. For each of the following types of spectra, describe a possible source and indicate how this information could be used by astronomers.

a. continuous spectrum

b. absorption spectrum (dark-line spectrum)

6c) emission spectrum(bright-line spectrum)

8. Sketch a series of diagrams to show the main steps in the evolution of stars like the Sun.