Question

a scientist is analyzing the oldest known mineral sample collected from the surface of mercury. it is discovered that 50% of the original amount of uranium - 238 remains in the sample.
question:
using the graph above, determine the age of mercury.
9000 million years (9 billion)
4500 million years (4.5 billion)
there is not enough evidence provided to answer this question
18000 million years (18 billion)

Explanation:

Step1: Recall the concept of half - life

The half - life of Uranium - 238 is the time it takes for half of the original amount of Uranium - 238 to decay. When 50% of the original amount of Uranium - 238 remains, one half - life has passed.

Step2: Know the half - life of Uranium - 238

The half - life of Uranium - 238 is approximately 4.5 billion years.

Answer:

4500 million years (4.5 billion)