Which sequence of formation is most likely to be correct, oldest to youngest?
A) globular clusters, open clusters, OB associations
B) Population I stars, population II stars, population III stars
C) halo, spiral arms, globular clusters
D) planetary nebulae, Population I stars, population II stars
E) emission nebulae, planetary nebulae, dark nebulae
A
You might also like to view...
What are the two primary components of the Ptolemaic Universe model?
What will be an ideal response?
Consider a set of hypothetical planets that are identical in their orbits and properties except they have different axis tilts. Which of the following axis tilts would give its planet the most extreme differences between their seasons? (Axis tilt is measured relative to a line drawn perpendicular to the planet's orbit.)
A) 23.5 degrees B) 90 degrees C) 0 degrees D) 45 degrees
The Permian extinction event was mostly likely caused by
A) widespread volcanic activity in Siberia B) an asteroid impact C) the onset of a snowball Earth phase D) the reversal of the Earth's magnetic field
A figure skater with arms initially extended starts spinning on the ice at 3 rad/s. She then pulls her arms in close to her body. Which of the following results?
a. a smaller rotational rate c. a greater angular momentum b. a greater rotational rate d. a smaller angular momentum