The a Half-Life of 5,715 Years

Multiple Choice

The a half-life of 5,715 years.After 2,000 years, a sample of the isotope is reduced to 1.2 grams.What was the initial size of the sample (in grams) ? How much will
Remain after 20,000 years (i.e., after another 18000 years) ? Round your answers to four decimal
Places.

A) 1.0706 , 0.0947
B) 2.4471 , 0.2164
C) 1.5294 , 0.1352
D) 2.1412 , 0.1893
E) 1.9883 , 0.1758