Under the doppler effect, an observer behind a moving wave source observes

What is the mass defect of a mole of nuclei with 1.8 x 10^15 j/mol binding energy?

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A4.86 g piece of metal was placed in a graduated cylinder containing 15.5 ml of water. the water level rose to 17.3 ml. what is the density of the metal. i need the steps of how to solve it to so i can use a formula to work out other problems.