<span>The half-life of a radioactive isotope describes the amount of time that it takes half of the isotope in a sample to decay. In the case of radiocarbon dating, the half-life of carbon 14 is 5,730 years. This half life is a relatively small number, which means that carbon 14 dating is not particularly helpful for very recent deaths and deaths more than 50,000 years ago. After 5,730 years, the amount of carbon 14 left in the body is half of the original amount. If the amount of carbon 14 is halved every 5,730 years, it will not take very long to reach an amount that is too small to analyze. When finding the age of an organic organism we need to consider the half-life of carbon 14 as well as the rate of decay, which is –0.693.</span>
There are certain solids able to do this some gas and few liquids
Metamorphic rocks are formed by physical or heat
The sporophyte produces 28
I would need more info to clarify, but I would believe this is an conclusion considering it's apart of the science project, which I assume is done.