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Author Question: Generally speaking, how does the surface temperature and luminosity of a protostar compare to the ... (Read 39 times)

deesands

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on: Jul 27, 2018
Generally speaking, how does the surface temperature and luminosity of a protostar compare to the surface temperature and luminosity of the main-sequence star it becomes?
 
  A) A main-sequence star is cooler and dimmer than it was as a protostar.
  B) A main-sequence star is cooler and brighter than it was as a protostar.
  C) A main-sequence star is hotter and brighter than it was as a protostar.
  D) A main-sequence star is hotter and dimmer than it was as a protostar.

Question 2

The gravitational lens effect has been verified by
 
  A) observations of multiple images of the same background galaxy seen towards a massive galaxy cluster.
  B) single images of highly distorted, high-redshift galaxies seen towards massive galaxy clusters.
  C) observations of the bending of starlight by the Sun during a 1919 eclipse.
  D) all of the above
  E) None of the above; this effect is purely hypothetical.


ju

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Reply #1 on: Jul 27, 2018
Answer to Question 1

D

Answer to Question 2

D


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