The disk of our galaxy consists of a. the nine known planets. ...

[londonang]

The disk of our galaxy consists of
 
  a. the nine known planets.
  b. only stars.
  c. stars, dust, and gas.
  d. quasars.
  e. only black holes.

Question 2

Due to the dust in the interstellar medium, a distant star will appear to an observer on Earth to be
 
  a. brighter and cooler than it really is.
  b. brighter and hotter than it really is.
  c. fainter and cooler than it really is.
  d. fainter and hotter than it really is.
  e. unchanged in brightness or apparent color.

[amy.lauersdorf90]

Answer to Question 1

c
RATIONALE: Refer to galaxy' on page 5.

Answer to Question 2

c