Respuesta :
1/2 of the original amount means 1 half life has passed. Since the half life is 1.3 billion years, the rock is 1.3 billion years old.
Answer:
Age of rock is 1.3 billion years
Explanation:
The half life of radioactive nuclide is 1.3 billion years
let us say that the original quantity of rock once upon a time would have been 100%
Half life period means the period in which the quantity of radioactive substance with in the nuclide reduces to half its original value.
Thus, time taken by nuclide to reduce to 50% of its original amount (i.e 100%, once upon a time) is 1.3 billion years.
Hence, it can be concluded that the time at which the nuclide has exactly 100% of its original amount would be 1.3 billion years.
Thus, the age of rock is 1.3 billion years.