The half-life of \[C{{o}^{60}}\] is 7 years. If one \[gm\] of it decays, the amount of the substance remaining after 28 years is [EAMCET 1992]

The half-life of \[C{{o}^{60}}\] is 7 years. If one \[gm\] of it dec

1.	The half-life of \[C{{o}^{60}}\] is 7 years. If one \[gm\] of it decays, the amount of the substance remaining after 28 years is [EAMCET 1992]
A.	\[0.25\,gm\]
B.	\[0.125\,gm\]
C.	\[0.0625\,gm\]
D.	\[0.50\,gm\]
Answer» D. \[0.50\,gm\]

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The half-life of \[C{{o}^{60}}\] is 7 years. If one \[gm\] of it decays, the amount of the substance remaining after 28 years is [EAMCET 1992]

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