Which Single Major Problem Perhaps Concerns Astronomers the Most as They

question 69

Multiple Choice

Which single major problem perhaps concerns astronomers the most as they attempt to interpret the properties and behavior of clusters of galaxies?

• A) The presence of star formation in many galaxies,long after it is expected to have died out
• B) The problem that at least 10 times more mass is needed for galactic cluster stability than is observed in visible material
• C) The structure and motion of spiral arms in galaxies in many clusters
• D) The excessive rate of supernova occurrence in galaxies in some clusters

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Definitions:

Cecum

The first section of the large intestine, connected to the ileum and acting as a junction for intestinal contents moving from the small to the large intestine.

Mesentery

A fold of the peritoneum that attaches the intestines to the posterior abdominal wall, holding them in place.

Peritoneal Fold

A fold in the lining of the abdominal cavity, which is part of the peritoneum, possibly covering or supporting abdominal organs.

Fluoroscopic Exam

A type of medical imaging test that shows a continuous X-ray image on a monitor, allowing for the real-time movement of internal structures.