A radioactive material of half-life `T` was kept in a nuclear reactor at two different instants. The quantity kept second time was twice of the kept first time. If now their present activities are `A_1` and `A_2` respectively, then their age difference equals
A. `T/(ln2)| l n (2A_(1))/(A_(2))|`
B. `T|l n(A_(1))/(A_(2))|`
C. `T/(ln2)|l n(A_(2))/(2A_(1))|`
D. `T ln |A_(2)/(2A_(1))|`
