The Milky Way Galaxy is
a. a spiral galaxy.
b. part of a cluster of galaxies that contains a few dozen galaxies.
c. about 80,000 light years in diameter.
d. All of the other choices are correct.
Question 2
If the distance to the nearest star is 4.2 light-years, then
a. the star is 4.2 million AU away.
b. the light we see left the star 4.2 years ago.
c. the star must have formed 4.2 billion years ago.
d. the star must be very young.
e. the star must be very old.