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Question
In the closed universe model, the geometry of spacetime in two dimensions resembles the surface of aA) flat piece of paper.
B) saddle.
C) cylinder.
D) sphere.
E) pyramid.
Answer
This answer is hidden. It contains 1 characters.
Related questions
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Why is the energy source for active nuclei like Seyferts thought to be compact?
A) The sources appear to be single stars in photos.
B) Their energy appears to be non-stellar synchrotron radiation.
C) The light can vary over short time intervals.
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