Skeletal Remains of the So-Called "Pittsburgh Man", Unearthed in Pennsylvania

Skeletal remains of the so-called "Pittsburgh Man", unearthed in Pennsylvania, had lost 74% of the carbon 14 they originally contained. Determine the approximate age of the bones. Hint: the decay constant k for carbon 14 is equal to 0.00012.

A) The approximate age of bones is 10,103 year(s) .
B) The approximate age of bones is 9,694 year(s) .
C) The approximate age of bones is 7,770 year(s) .
D) The approximate age of bones is 11,226 year(s) .