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

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Definitions:

Human Hormones

Chemical substances produced in the body that regulate and control the activity of certain cells or organs.

Herbicides

Chemical substances used to control or kill unwanted plants (weeds).

Transgenic Organisms

Transgenic organisms have had genes from other species inserted into their genetic code, allowing them to express traits that are not naturally theirs.

Plant Cell

The basic structural and functional unit of plants, distinguished by having a cell wall, chloroplasts, and a central vacuole.