Atoms And Nuclei

Atomic masses of two oxygen isotopes ${ }_8^{16} \mathrm{O}$ and ${ }_8^{18} \mathrm{O}$ are 15.99491 u and 17.99916 u , respectively, where $u$ is the atomic mass unit. Masses of protom and neutron are given by 1.00727 u and I .00866 u , respectively. The speed of light is c . What is the difference between the binding energies of ${ }_8^{18} \mathrm{O}{ }_8^{16} \mathrm{O}$ nuclei in units of $u c^2$ ?