A Rock Contains 0 $\rarr$ Pb-206 Is 4

question 37

Multiple Choice

A rock contains 0.37 mg of Pb-206 and 0.95 mg of U-238. The half-life of the decay series U-238 $\rarr$ Pb-206 is 4.5 * 10⁹ yr. Assuming no Pb-206 was present in the rock initially, how old is the rock

• A) 1.7 * 10⁹ yr
• B) 5.2 * 10⁹ yr
• C) 2.7 * 10⁶ yr
• D) 4.5 * 10⁹ yr
• E) 2.4 * 10⁹ yr

---

Definitions:

RMSE

Root Mean Square Error, a measure of the magnitude of differences between values predicted by a model or an estimator and the values observed.

Industrial Lathe Sales

The commercial activity involving the buying and selling of industrial lathes, which are machines used for shaping metal, wood, or other materials.

Regression Method

A statistical approach for determining the relationship between a dependent variable and one or more independent variables.

Industrial Lathe Sales

The total revenue or the number of transactions related to the sale of industrial lathes, which are machine tools used for shaping materials.