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