Answer
$28.296MeV$
Work Step by Step
First of all, we find the mass of two protons, two neutrons and two electrons:
$m_f=2(1.007276u)+2(1.008665u)+2(0.000549u)$
$\Delta m=m_f-m_i$
$\implies \Delta m=4.03298u-4.002603u=0.030377u$
Now $E=mc^2$
$\implies E=0.030377u(\frac{931.49MeV}{1u})$
$E=28.296MeV$
