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Two radioactive elements A and B initially have same number of atoms. The half life of A is same as the average life of B. If λ A and λ B are decay constants of A and B respectively, then choose the correct relation from the given options.

1. λ A l n2 = λ B
2. λ A = λ B
3. λ A = λ B ln2
4. λ A = 2λ B

Correct answer: λ A = λ B ln2

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