A galaxy's supermassive black hole represents about ____ for ...

[penza]

A galaxy's supermassive black hole represents about ____ for elliptical galaxies.
 
  a. half a percent of the mass of the disk
 b. five percent of the mass of the central bulge
  c. half a percent of the mass of the central bulge
  d. five percent of the mass of the disk
 e. half a percent of the dark matter in the corona

Question 2

Physicists and astronomers usually refer to the permitted orbits of an atom as the atom's _______________ levels.
 
  Fill in the blank(s) with correct word

[asware1]

Answer to Question 1

c

Answer to Question 2

energy

[penza]

Excellent

[Kedrick2014]

Gracias!