A radioactive isotope has a half-life of 5,000 years. A rock originally contained 16 grams of radioactive isotope, and now contains 4 grams. Approximately how many years old is the rock?

10,000 years

Explanation:

Given that,

Half life of the radioactive isotope, = 5000 years

Initial composition, = 16 grams

Final composition, = 4 grams

We know that,

Therefore, the age of the rock is 10,000 years.

i think it because equal matrices have equal dimensions, only square matrices can be symmetric. for all indices and . every square diagonal matrix is symmetric, since all off-diagonal elements are zero. in linear algebra, a real symmetric matrix represents a self-adjoint operator over a real inner product space.