The Andromeda spiral galaxy is almost edge-on to us. Astronomers ...

[james0929]

The Andromeda spiral galaxy is almost edge-on to us. Astronomers have detected the orbital motion of this and other such galaxies' disk material by
 
  a. using Hubble's law.
  b. measuring Doppler shifts of different parts of the disk.
  c. the steady state theory.
  d. measuring Doppler shifts of different parts of the disk.

Question 2

Stars that have ejected a planetary nebula eventually become
 
  a. protostars.
  b. brown dwarfs.
  c. white dwarfs.
  d. red giants.

[SAUXC]

Answer to Question 1

d

Answer to Question 2

c

[james0929]

TYSM

[Viet Thy]

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