Answer:
The rock is 3.75 billion years ago.
Explanation:
Given that:
Half life = 1.25 billion years
1 billion years = 10⁹ years
So,
Half life = 1.25 × 10⁹ years

Where, k is rate constant
So,


The rate constant, k = 5.5452 × 10⁻¹⁰ years⁻¹
Initial amount [A₀] = 80 micrograms
Final amount
= 10 micrograms
Using integrated rate law for first order kinetics as:
![[A_t]=[A_0]e^{-kt}](https://tex.z-dn.net/?f=%5BA_t%5D%3D%5BA_0%5De%5E%7B-kt%7D)
So,





So,
<u>The rock is 3.75 billion years ago.</u>
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The philosophy of Libertarian model supports individuality and freedom of thought. No one is subject to authority, and everyone is free to express their views. Furthermore, there is no censorship, and the government has no right to impose restrictions on the media.
According to libertarian doctrine, media should be privately held. The philosophy supports individuality and freedom of thought. No one is subject to authority, and everyone is free to express their views. Furthermore, there is no censorship, and the government has no right to impose restrictions on the media.
To learn more about Libertarian model here,
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I think it’s the very last one to redraw it’s borders,