Multiple Choice
Suppose we observe a source of X-rays that varies substantially in brightness over a period of a few days.What can we conclude?
A) The X-ray source is a quasar.
B) The X-ray source contains a black hole with an accretion disk.
C) The X-ray source is no more than a few light-days in diameter.
D) The X-ray source must have a strong,rapidly varying magnetic field.
Correct Answer:
Verified
Correct Answer:
Verified
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