1. The Suns 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, B23. 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?