Author Question: What kind of variable stars are pre-Main Sequence stars undergoing gravitational contraction and ... (Read 93 times)

ishan

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What kind of variable stars are pre-Main Sequence stars undergoing gravitational contraction and exhibiting erratic changes in their luminosities?
 
  A) R Coronae Borealis
  B) RR Lyrae
  C) Cepheid
  D) T Tauri
  E) Herbig-Haro

Question 2

What information about an astronomical object can be determined by observing its spectrum?
 
  A) its temperature
  B) its radial motion
  C) its chemical composition
  D) whether it has a strong magnetic field
  E) All of the above



chreslie

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Answer to Question 1

D

Answer to Question 2

E



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