A projectile is to be launched at an angle of 30° so that it falls beyond the pond of length 20 meters as shown in the figure. A) What is the range of values of the initial velocity so that the projectile falls between points M and N?

It compares the the difference between a radioactive element remaining in specimen to the amount of the radioactive element that would have been originally trapped in the specimen. This is done by comparing the ratio of the relative abundance of this radioactive element to its non radioactive isotope in nature to their ratio remaining in the specimen and comparing it to the half-life of the radioactive isotope.