2) Carbon 14 has always decayed at the same speed.
While most scientists believe that carbon 14 has always decayed at the same rate (or speed) there are some who now believe it is slowing down and could have decayed much faster only a couple thousand years ago . . . that means when they use it to date things today, the dates will be much much older than they really are.
3) All living things absorb the same amount of carbon 14 as the atmosphere has in it.
Scientists have found animals living which when dated by carbon 14 are found to be thousands of years old - how can this be if they are still living?
The most important "assumption" people make when using carbon 14 (or any other dating meathod) is that the world is billions of years old. I make another "assumption" I assume the Bible is right when it says the world is about 6,000 years old. And I think the evidence fits the Bible better too.
What is your assumption? Do you believe evolution as many people do today? Or do you believe the Bible?
Write and let me know - And be watching as you will be finding more evidence here on Kidspot that the Bible is and always has been right!