A radioactive sample of U238 decay to Pb through a process for which h – McqOptions

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1.	A radioactive sample of U238 decay to Pb through a process for which half life is 4.5 ´ 109 years. The ratio of number of nuclei of Pb to U238 after a time of 1.5 ´ 109 years (given 21/3 = 1.26) [Based on IIT-JEE (Mains) 2004]
A.	0.12
B.	0.26
C.	1.2
D.	0.37
Answer» C. 1.2

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