Concerning dark energy, we do know:

A) that it is created when matter annihilates anti-matter.
B) its density remains constant over time, so it is not important in the early Universe.
C) combined with dark matter, it will ultimately produce a closed universe.
D) that it was revealed with Type II supernovae distances in the late 1990s.
E) that it makes up 90% of all the matter and energy in the whole universe.


B

Physics & Space Science

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Indicate whether the statement is true or false

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In 2014, when scientists used a laser to simulate the conditions generated when a large impact hits a mixture of prebiotic molecules, they were able to produce

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An electron, starting from rest and moving with a constant acceleration, travels 2.0 cm in 5.0 ms. What is the magnitude of this acceleration?

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