A. more fuel and a longer life.
B. more fuel and a shorter life.
C. less fuel and a shorter life.
D. less fuel and a longer life.
E. You can’t say from the given information.
A white dwarf
A red giant
A. disk of stars with our Solar System near the edge.
B. disk of stars centered on our Solar System.
C. disk of stars with a bulge containing our Solar System.
D. sphere of stars centered on our Solar System.
E. sphere of stars with our Solar System near the edge.
A. Clouds in the Milky Way
B. Distant galaxies
C. Local group galaxies
D. Nearby stars
E. All of the above
A. the density of the Universe is less than the critical density.
B. the Universe has a center and an edge.
C. gravity is strong enough to stop the expansion in a finite time.
D. the Hubble Constant is less than 50 km/s/Mpc.
E. holiday shopping hours are restricted.
A. circular stellar orbits
B. high metal abundance
C. young stars
D. randomly inclined stellar orbits
E. active star formation regions
A. contained in the massive O and B stars in the galaxy.
B. contained in the H I regions of the galaxy.
C. contained in the H II regions of the galaxy.
D. contained in the dark matter of the galaxy.
E. contained in the disk of the galaxy
A. There is no center.
B. the Earth
C. the Sun
D. the Milky Way
E. the Big Bang
A. old stars destroy heavy elements as they age.
B. the heavy elements were made in previous generations of stars.
C. young stars burn their nuclear fuels faster.
D. heavy elements haven’t had time to settle to the core of these younger stars.
E. all of the above.