Determine the mass defect (in atomic mass units) for (a) helium , which has an atomic mass

Question:

Determine the mass defect (in atomic mass units) for (a) helium, which has an atomic mass of 3.016030 u, and (b), which has an atomic mass of 3.016050 u. (c) On the basis of your answers to parts (a) and (b), state which nucleus requires more energy to disassemble it into its separate and stationary constituent nucleons. Give your reasoning.