Question

The following graph shows the rates of decay for four parent isotopes. Based on the graph, which parent isotope most likely has a half-life of 13 billion years?
A

B

C

D

Answer 1

Just look at the graph, and find a curve that has fallen to
half of its original value 95 = 47.5 in 13 B years.

Do I really hafta tell you which one it is ?

















It's curve ' C ' .

Answer 2

The answer is A.                                                            

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