A radioactive isotope has a half-life of 10 days. If today \[125\,mg\]is left over, what was its original weight 40 days earlier [KCET 2005]

A radioactive isotope has a half-life of 10 days. If today \[125\,mg\]

1.	A radioactive isotope has a half-life of 10 days. If today \[125\,mg\]is left over, what was its original weight 40 days earlier [KCET 2005]
A.	2g
B.	600 mg
C.	1 g
D.	1.5 g
Answer» B. 600 mg

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A radioactive isotope has a half-life of 10 days. If today \[125\,mg\]is left over, what was its original weight 40 days earlier [KCET 2005]

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