A Geological Sample Is Found to Have a Pb-206/U-238 Mass

question 15

Multiple Choice

A geological sample is found to have a Pb-206/U-238 mass ratio of 0.337/1.00.Assuming there was no Pb-206 present when the sample was formed,how old is it? The half-life of U-238 is 4.5 × 10⁹ years.

• A) 7.3 × 10¹¹ years
• B) 1.4 × 10¹⁰ years
• C) 2.4 × 10¹⁰ years
• D) 2.1 × 10⁹ years
• E) 7.1 × 10⁹ years

---

Definitions:

Erikson

A psychologist known for his theory on the psychosocial development of humans, outlining eight stages from infancy to adulthood.

Volunteer Activities

Unpaid tasks or services performed by individuals or groups to benefit others or the community as a whole.

Civic Responsibility

The duties and responsibilities of a citizen to be active, informed, and engaged in their community and society.

Hormonal Changes

Variations in the levels of hormones in the body, which can affect physical and emotional health, and are often associated with puberty, menstruation, pregnancy, and menopause.