<span>When a red giang complete helium fusion and collapses, it becomes a white dwarf. The correct option is C. White dwarf are very dense stars that are usually the size of a planet. It is a stellar core reminant which mainly made up of electron degenerated matters; its mass is comparable to that of the sun while its volume is comparable to that of the earth. </span>
Iodine-131 has a half life of 8 days, so half of it is gone every 8 days.
10 grams of iodine-131 is left for 24 days.
At 8 days: 10/2=5 grams left
At 16 days: 5/2=2.5 grams left
At 24 days: 2.5/2=1.25 grams left.
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Your mistake is that you stopped at 16 days.
Answer:
Electromagnetic waves do not require any medium to travel whereas mechanical waves must have a medium to propagate.
So, Basically, it is B I believe.
Hope It Helps!
