According to the unified model calculations, if you look directly into the central cavity around the ...

According to the unified model calculations, if you look directly into the central cavity around the black hole of a galaxy, you would see a:
 
  A) very luminous source with few or no emission lines.
  B) large Doppler shift with broad spectral lines.
  C) small Doppler shift with narrow spectral lines.
  D) jet emerging parallel to the accretion disk.

Question 2

Which of the following is true of rich galaxy clusters?
 
  A) They primarily consist of irregular galaxies.
  B) More than 80 percent of their galaxies are spiral galaxies.
  C) Less than 20 percent of their galaxies are E and S0 galaxies.
  D) They often contain one or more giant elliptical galaxies at their centers.

Question 3

Which of the following is true of poor galaxy clusters?
 
  A) They contain about 1500 to 2500 galaxies.
  B) They primarily contain elliptical galaxies.
  C) They are densely crowded toward the center.
  D) They are irregularly shaped.

Question 4

Identify a true statement about quasars.
 
  A) Their spectra are similar to the spectra of stars.
  B) Their spectra do not show any redshift.
  C) They exhibit fluctuations in their brightness over time scales of hours or minutes.
  D) They are supermassive structures with a diameter of 20 to 50 Mpc.