Answer:
Amy: 8, Ben: 3
Step-by-step explanation:
No explanation here
Answer:WFG=116
A. 2.8 billion years old
1/16 = (1/2)^4, so 4 half-lives have elapsed.
4 · 0.700 billion years = 2.8 billion years
The rock is 2.8 billion years old.