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Author Question: Which of the following is thought to be a black hole? a. Gleise 229B b. Sirius B c. Orion Nebula ... (Read 38 times)

ghost!

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Which of the following is thought to be a black hole?
 a. Gleise 229B
  b. Sirius B
  c. Orion Nebula
  d. Cygnus X-1

Question 2

When a hydrogen atom's electron goes from an energy state of n = 1 to n = 3,
 a. the radius of the electron's orbit is unchanged.
  b. the radius of the electron's orbit is increased.
  c. the radius of the electron's orbit is decreased.
  d. the radius of the electron's orbit is infinite.



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lcapri7

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Answer to Question 1

d

Answer to Question 2

b




ghost!

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Reply 2 on: Jul 28, 2018
Gracias!


milbourne11

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Reply 3 on: Yesterday
Thanks for the timely response, appreciate it

 

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