Based on the graph, 2 half-lives equals

Question

Responses
A 4.5 billion years.4.5 billion years.
B 9 billion years.9 billion years.
C 12.5 billion years.12.5 billion years.
D 18 billion years.

Answer 1

To determine the answer based on the concept of half-lives, we need to understand what a half-life indicates. A half-life is the time required for half of a substance to decay or transform into another substance.

If you are referring to a specific substance (like Uranium-238, which has a half-life of about 4.5 billion years), then:

• 1 half-life = 4.5 billion years
• 2 half-lives = 2 × 4.5 billion years = 9 billion years

So, the correct answer would be:

B. 9 billion years.