formula and explanation please

Atoms consist of a nucleus made up of protons and neutrons. Orbiting outside the nucleus are a "cloud" of electrons. The number of protons determines the element. A carbon atom contains six protons and (normally) six neutrons; however, certain isotopes of carbon can exist. An isotope occurs when an atom has a different number of neutrons. Isotopes of carbon include: Carbon-12, Carbon-13, and Carbon-14. 6 protons 6 neutrons electron + proton neutron Carbon atom Figure 1: Depiction of a carton adom Carbon is an element common in living (organic) matter with C-12 and C-14 occurring in similar abundances. These isotopes combine with Oxygen to form Carbon Dioxide which plants use in photosynthesis. When these plants die, the C-12 and C-14 decay at diferent rates. (Radioactive decay occurs when an atom decays into a different element. Carbon-14 decays to Nitrogen-14 ) Radiocarbon dating is a common technique used to find the age of dead organic matter by measuring the difference between C-12 and C-14 in a sample. This sample could be an ancient plant or animal. Use the C-14 curve below to answer the questions in the discussion section. Data The plot here represents the length of time between C-14 decays: X-Exp(X) Use this plot to answer the questions that follow. () - 5000121 20.000 40-800 What is the probability of a C-14 atom taking less than 7,000 years to decay? P(X