An analysis of the rock shows that the relative number of `Sr^(87)` and `Rb^(87) (t_(1//2)=4.7 xx10^(10)` year) atoms is 0.05 . What is the age of the rock? Assume all the `Sr^(87)` have been formed from `Rb^(87)` only
a) `7.26 xx10^(9)` year
b) `1.43 xx 10^(9)` year
c) `3.28 xx 10^(9)` year
d) `4.32 xx10^(8)` year

Options

A. `7.26 xx10^(9)` year
B. `1.43 xx 10^(9)` year
C. `3.28 xx 10^(9)` year
D. `4.32 xx10^(8)` year

Answer

C