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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 11 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
Wow, this really help


mochi09

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Reply 3 on: Yesterday
Excellent

 

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