Question

which characteristic of potassium makes it useful for dating rocks? it has a long half - life. it decays at an unknown rate. it produces lead as it breaks down. it can be used to date all types of rock.

Explanation:

Potassium - argon dating is a common radiometric dating method. Potassium - 40 has a long half - life of about 1.25 billion years, which allows it to be used to date old rocks. The decay rate is known, it doesn't produce lead on breakdown, and it can't date all types of rock.

Answer:

It has a long half - life.