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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 26 times)

ghost!

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on: Jul 28, 2018
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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Reply #1 on: Jul 28, 2018
Answer to Question 1

d

Answer to Question 2

b


ghost!

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Reply 2 on: Jul 28, 2018
Great answer, keep it coming :)

helenmarkerine

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Reply 3 on: Yesterday
:D TYSM

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