Author Question: Based on inventoried matter in the universe, including dark matter known to exist in galaxies and ... (Read 47 times)

evelyn o bentley · **on:** Jul 27, 2018

Based on inventoried matter in the universe, including dark matter known to exist in galaxies and clusters, the actual density of the universe is what fraction of the critical density?

A) 1 percent
B) 10 percent
C) 26 percent
D) 74 percent
E) 100 percent

Question 2

What can we detect from matter that has crossed an event horizon?

A) Gamma-ray bursts
B) Radio waves if the matter was traveling fast enough
C) Visible light
D) X-rays if the matter was dense
E) Nothing