Multiple Choice
The Ring Nebula is a planetary nebula that currently has a radius of 1.2 × 1013 km and an expansion velocity of 250 km/s.Approximately how long ago did its parent star die and eject its outer layers?
A) 1,500 years ago
B) 3,200 years ago
C) 5,400 years ago
D) 8,000 years ago
E) 28,000 years ago
Correct Answer:

Verified
Correct Answer:
Verified
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