Based on the observed amount of deuterium in the universe, we can conclude that

A) neutrons outnumber protons 7 to 1 in the universe.
B) most of the deuterium that was created during the era of nucleosynthesis has since been destroyed.
C) we live in a critical-density universe.
D) the density of ordinary (baryonic) matter is about 5 percent of the critical density.
E) ordinary (baryonic) matter makes 75 percent of the mass of the universe.


D

Physics & Space Science

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