If You Obtained a Sample of Rock from Venus and Determined

question 51

Multiple Choice

If you obtained a sample of rock from Venus and determined the abundances of uranium (²³⁸U) and lead (²⁰⁷Pb) in it, and found that for every one uranium atom there were three lead atoms, then what would the age of this rock be? Note that this form of uranium decays to this form of lead with a half-life of 700 million years. For simplicity, you can assume that there was no lead in the rock when it originally formed.

• A) 1.4 billion years
• B) 2.8 billion years
• C) 4.0 million years
• D) 10.5 billion years
• E) 3.6 billion years

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Definitions:

Estimate

An approximate calculation or judgment of the value, number, quantity, or extent of something.

Coefficient of Determination

A statistical measure, often denoted as R², that represents the proportion of the variance in the dependent variable that is predictable from the independent variable(s).

Coefficient of Correlation

A numerical metric that determines the intensity and course of a straight-line association between two variables that can be quantified.

Sample Coefficient

A measure that quantifies some kind of property or behavior, such as variability or correlation, from a sample of a population.