Atoms of carbon-14 are radioactive. The decay into atoms of the element nitrogen. Suppose that a sample of rock is taken from a fossil. The sample has 1000 of carbon-14 and 1000 atoms of nitrogen. If carbon-14 has a half-life of 5700 years, how old is the fossil ?

A. 2850 years old
B. 5700 years old
C. 17,100 years old
D. 11,400 years old

Directions: read the descriptions of the four islands presented in the lesson. 1. list two new traits that each new species of rat might demonstrate as it adapts to the conditions on each island. 2. introduce one of the four new rat species to another island and describe one challenge it would encounter and one success as it adapts to its new environment.