Author Question: Ordinary matter makes up approximately ____percent of the critical density of the Universe. a. ... (Read 28 times)

TVarnum

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Ordinary matter makes up approximately ____percent of the critical density of the Universe.
 
  a. 0.1
  b. 1
 c. 4.5
  d. 10
 e. 50

Question 2

How many nuclear reactions occur in a proton-proton chain?
 
  a. two
 b. three
  c. one
 d. four
 e. five



al

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Answer to Question 1

c

Answer to Question 2

b



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