The orbits of population I stars I. are confined to disk of the galaxy. II. are very elliptical. III. are nearly circular. IV. are randomly inclined to the disk of the galaxy.
a. I
b. IV
c. I & IV
d. II & IV
e. I & III
Question 2
Opacity is
a. the balance between the pressure and force of gravity inside a star.
b. the force that binds protons and neutrons together to form a nucleus.
c. the force that binds an electron to the nucleus in an atom.
d. a measure of the resistance to the flow of radiation (photons) through a gas.
e. the temperature and density at which a gas will undergo thermonuclear fusion.
During their annual migration, the entire population of Arctic terns move from the Arctic Ocean in t
Rising and Setting of Stars at Middle North Latitudes
Evolution of Stars Off the Main Sequence
Peculiar Galaxy NGC 5128 (Centaurus A)
Cotton Production and Slave Population, 1800–1860
Human Population Growth