Multiple Choice
If gravity alone acts to retard the expansion and nothing acts to accelerate it, the Universe is said to be closed if
I.gravity is strong enough to stop the expansion in a finite time.
II.the density of the Universe is less than the critical density.
III.the Universe is finite.
A) I & II
B) I & III
C) II & III
D) I, I, & III
E) None of the other choices are correct.
Correct Answer:

Verified
Correct Answer:
Verified
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