Fossils up to 75,000 years old can be dated with Carbon-14.
Radio isotopes can be used for the age determination of the fossils. Carbon-14 is a common isotope which is used for that purpose. But the half- life of the Carbon-14 is relatively small as 5730 years. That means the amount of Carbon-14 will be half after every 5730 years. Hence, decay is very fast. So Carbon-14 cannot be used forage determination which is more than 75000 years due to the low accuracy.
Answer:
Right now, I am in college for climatology, but before I decided on climatology, I was taking classes in Meteorology, the study of weather. So, I will answer your question. All meteorologists like to be right, but since the weather is so spontaneous, it is really hard to be right. Meteorologists use percentages because it helps them be professional. Also, because, different parts of the region where they are may or may not get the rain. I don't know where you are from, but I will use my hometown. In McAlester, Oklahoma, there may be a 70% chance of rain, but in another part of the region at Tulsa, Oklahoma ( which is 91 miles north of McAlester) there may be a 40% chance of rain. The difference in the percentages can vary from how stable the environment is, altitude, location, and terrain. That is two of the reasons why Meteorologists use percentages to predict weather.
Explanation:
In semiconservative DNA replication, each new double helix that will form will have 1 polynucleotide strand that is from the old DNA molecule and is an Old or Parent strand, and will have a polynucleotide strand from the newly synthesized one, the new DNA strand.
