The Rb-87/Sr-87 Method of Dating Rocks Is Often Used by Geologists

question 71

Multiple Choice

The Rb-87/Sr-87 method of dating rocks is often used by geologists: t_1/2 = 6.0 × 10¹⁰ yr Estimate the age of a rock sample in which the present-day mole ratio of Rb-87 to Sr-87 is 36:1.

• A)2.4 × 10⁹ yr
• B)1.7 × 10⁹ yr
• C)3.1 × 10¹¹ yr
• D)4.1 × 10^-11 yr
• E)3.6 × 10¹¹ yr

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