500
                                Protons and neutrons make up the nucleus of an atom and are the most massive particles in the atom.  In fact, if a nucleus were the size of an average grape, it would have a mass greater than 9 million metric tons.  A metric ton is 1000kg.  What would the mass of a grape size nucleus be in kgs?  Write your answer in Scientific Notation.
                                What is 9 x 10^9   or 9.0 x 10^9