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Author Question: The look-back time is a. the time it takes for the light from an object to reach Earth. b. ... (Read 98 times)

vinney12

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on: Jul 27, 2018
The look-back time is
 
  a. the time it takes for the light from an object to reach Earth.
  b. numerically equal to the distance in light-years.
  c. smaller for more distant objects.
  d. All of the other choices are correct.
  e. the time it takes for the light from an object to reach Earth and numerically equal to the distance in light-years.

Question 2

HII regions are found near stars cooler than 25,000 K because large amounts of ultraviolet photons would totally destroy the hydrogen atoms in the gas.
 
  a. True
  b. False
  Indicate whether the statement is true or false


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flexer1n1

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

e

Answer to Question 2

False


vinney12

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Reply 2 on: Jul 27, 2018
Excellent

AISCAMPING

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Reply 3 on: Yesterday
Wow, this really help

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