Multiple Choice
Type II supernovae show prominent lines of hydrogen in their spectra,whereas hydrogen lines are absent in spectra of Type Ia supernovae.Why is this? (Hint: Think about the type of star that gives rise to each of the two types of supernova. )
A) Massive stars have burned all of their hydrogen into heavier elements,whereas low-mass stars still have large hydrogen-rich envelopes.
B) Massive stars contain large amounts of hydrogen,whereas white dwarfs are mostly carbon and oxygen.
C) White dwarfs have a thick surface layer of hydrogen,whereas neutron stars contain no hydrogen at all.
D) Massive stars contain large amounts of hydrogen,whereas neutron stars contain no hydrogen at all.
Correct Answer:

Verified
Correct Answer:
Verified
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