Multiple Choice
Today,uranium contains 

(half-life = 0.70 billion years) and 

(half-life = 4.5 billion years) .At a time 1.9 billion years ago,what was the fraction of 
In uranium?
A) 3.53%
B) 4.72%
C) 4.90%
D) 6.76%
Correct Answer:

Verified
Correct Answer:
Verified
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