The Argon-40 Method of Radioisotope Dating Was Developed in the Geology

question 26

Multiple Choice

The argon-40 method of radioisotope dating was developed in the Geology Department at Stony Brook University to determine the age of rocks brought back from the moon.This method assumes that no ⁴⁰Ar gas was trapped when the molten rock solidified,and that no ⁴⁰Ar could escape from the solid rock.One sample that was analyzed had a ⁴⁰K to ⁴⁰Ar ratio of 0.100 (N_K/N_Ar = 0.100) .⁴⁰K decays into ⁴⁰Ar by positron emission with a half-life of 1.28 10⁹ years.How many years ago was this moon rock formed?

• A)2.6 10⁸ years
• B)2.3 10⁹ years
• C)4.4 10⁹ years
• D)1.3 10¹⁰ years
• E)1.3 10⁸ years

---

Definitions:

Government

The system or group of people governing an organized community, often a state, and the mechanisms through which state policy is enforced and affairs of the state are conducted.

Invention

Invention is the creation of a new product, process, or idea that has not existed before, often leading to technological advancements and innovation.

Innovation

The process of translating an idea or invention into a good or service that creates value or for which customers will pay.

Invention

The creation of a product or introduction of a process for the first time.