What do we mean by the interstellar medium?

What do we mean by the interstellar medium?
 
  A) The gas and dust that lies in between the stars in the Milky Way Galaxy.
  B) The dust that fills the halo of the Milky Way Galaxy.
  C) The middle section of the Milky Way Galaxy.
  D) The name of an oracle who can channel messages from beings that live near the star called Vega.

Question 2

Why are most meteorites found in Antarctica?
 
  What will be an ideal response?

Question 3

The force of gravity between two objects
 
  A) increases with the masses of the bodies, but decreases with their separations.
  B) increases with the masses of the bodies, but decreases with the square of the distances between them.
  C) increases with the square of their masses, but decreases with the cube of their periods of orbit about the Sun.
  D) depends on the density, not the mass of the bodies.
  E) depends on the temperature, density, and size of the bodies.

Question 4

More massive stars are able to form in a ________ time than less massive stars.
 
  Fill in the blank(s) with correct word