There are 4 electrons altogether shared between carbon atoms in a molecule of C2H4, to be more precise there are 2 electron pairs shared between the carbon atoms.
It has not. Evolution is not a process that can happen to individual organisms; it's change that happens to a species over many generations.
Multiply 5730 years by 2 since two half-lives have gone by for carbon.
<u>Explanation</u>:
The half-life of a radioactive isotope depicts the measure of time that it takes half of the isotope in an example decay. On account of radiocarbon dating, the half-existence of carbon 14 is 5,730 years
The half-life of carbon-14 is 5730 years.
In this manner, after
1 half-life there is 50 % = 1/2 of the first amount left.
2 half-lives there is 25 % = 1/4 of the first amount left.
25% is two half-lives.
Every 50% of life requires 5730 years.
So two half-lives require 2 × 5730