The correct answer is:
[tex]2.79 \cdot 10^3 MeV[/tex]
Let's see why.
1 amu corresponds to the mass of the proton, which is:
[tex]m_p = 1.66 \cdot 10^{-27} kg[/tex]
if we convert this into energy, using Einstein equivalence between mass and energy, we find:
[tex]E=mc^2 = (1.66 \cdot 10^{-27} kg)(3\cdot 10^8 m/s)^2 = 1.49 \cdot 10^{-10} J[/tex]
Now we can convert it into electronvolts:
[tex]E= \frac{1.49 \cdot 10^{-10}kg}{1.6 \cdot 10^{-19} J/eV} =9.34 \cdot 10^9 eV = 934 MeV[/tex]
So, 1 amu = 934 MeV. Therefore, 3 amu corresponds to 3 times this value:
[tex]3 amu = 3 \cdot 934 MeV \sim 2790 MeV = 2.79 \cdot 10^3 MeV[/tex]
