Neutron stars and black holes are formed by:
A) the star formation process.
B) mass transfer in binary star systems.
C) novae.
D) type I supernovae.
E) type II supernovae.
Question 2
Astronomers believe that the Moon did not differentiate to the same degree as Earth because:
A) the Moon was made of solid debris, not liquids like our hydrosphere.
B) the meteors that hit the Moon were lighter than those that hit us, so did not generate as much heat on the surface.
C) the less dense and smaller Moon did not have as much radioactivity as the larger Earth in its core.
D) the Moon was formed after the Earth was, so its radioactivity was less.
E) the Moon was made of very different materials than our mantle and crust.