<h2>
Half Life</h2>
The half life period is the time in which only half of the given population remains. It can be represented through this equation:

- <em>t</em> = time passed
- <em>a</em> = y-intercept
- <em>h</em> = half life
<h2>Solving the Question</h2>
We're given:
- <em>h</em> = 28 million years
- <em>a</em> = 184 grams (this is the initial mass, after 0 time has passed)
For most questions like this, we would have to plug these values into the equation mentioned above. However, this question asks for the time elapsed after 3 half-lives.
This can be calculated simply by multiplying the given half-life by 3:
28 million years x 3
= 84 million years
<h2>Answer</h2>
84 million years
<h2>
<u>Answer:</u></h2>
⟶ 2³ × 3² is the prime factorization for which one of these choices?
Let's check,
1) 6 = 3 × 2 [So, obviously not this choice]
2) 25 = 5 × 5 = 5² [Not this either]
3) 36 = 3 × 2 × 2 × 3 = 3² × 2² [Doesn't match with 2³ × 3²]
4) 72 = 2 × 2 × 2 × 3 × 3 = <u>2</u><u>³</u><u> </u><u>×</u><u> </u><u>3</u><u>²</u><u> </u>[Matches]
⟶ The answer is, choice <u>7</u><u>2</u><u>.</u>
