1. The Sun's atmosphere has three layers. What are they called and what is their temperature?
2. (a) Stars are identified with a spectral type. What are the spectral types from hottest to coolest?
(b) Rank the following spectral types from hottest to coolest: A6, M2, O8, B4, B2
3. What is the structure of the H-R Diagram? What does it tell us?
4. Describe the characteristic behavior of RR Lyrae and Cepheid variables.
5. What determines if a Cepheid variable star is a Type I or Type II?