Respuesta :

Greenleafable
(2) U-238 is the radioisotope used in dating geological formations. Uranium-238 has a half-life of 4.46 billion years, which makes it suitable to date such old formations.
The other options do not have such long durabilities and half-lives.

Answer:

U- 238

Explanation:

Uranium-238 is used to date many geological samples, especially on materials that are thousands to over a million years old