Precise measurements give the following masses:

nuclide mass particle mass
¹₁H 1.0078 u ¹₀n 1.0086649 u
⁴₂He 4.00260 u ₋₁⁰e 5.485810⁻⁴ u
₁⁰e 5.485810⁻⁴ u

Now consider the following nuclear reaction:
2 ¹₁H + 2 ¹₀n → ⁴₂He

1) Is energy released or absorbed by this reaction?

a) Released.
b) Absorbed.
c) Neither released nor absorbed.
d) I need more information to decide.

2) If you said energy was released or absorbed, calculate how much energy is released or absorbed. Give your answer in both kJ/mol and MeV. Round each of your answers to significant digits.
Note: take particular care to keep enough digits in any intermediate calculation, and use enough digits in any scientific constants you need, since the data with which you are working are very precise.