Question 1052586
A centigram is (1/100) of a gram
(1/2)^n=0.99; n log(1/2)=log (0.99)
-n log (2)=log (0.99)
-0.30103n=-0.00436
n=0.00436/0.30103
n=0.1448 half lives
0.0145*1590=23.03 years
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