In the proton-proton cycle in the Sun,the energy released when an electron and its antiparticle combine is $\qquad$ .

If $1 \, g$ of hydrogen is converted into $0.993 \, g$ of helium in a thermonuclear reaction,the energy released in the reaction is ......... $J$.

What is a moderator? Name the material used as a moderator in a nuclear reactor.

Statement $1$: Energy is released when a heavy nucleus undergoes fission and when light nuclei undergo fusion.
Statement $2$: For heavy nuclei,the binding energy per nucleon decreases as $Z$ increases. For light nuclei,the binding energy per nucleon increases as $Z$ increases.

$A$ certain mass of Hydrogen is changed to Helium by the process of fusion. The mass defect in the fusion reaction is $0.02866 \, u$. The energy liberated per $u$ is ........... $MeV$. (Given $1 \, u = 931 \, MeV$)

Match the nuclear processes given in column $I$ with the appropriate option$(s)$ in column $II$.

Column $I$	Column $II$
$A$. Nuclear fusion	$P$. Absorption of thermal neutrons by ${}_{92}^{235}U$
$B$. Fission in a nuclear reactor	$Q$. ${}_{27}^{60}Co$ nucleus
$C$. $\beta$-decay	$R$. Energy production in stars via hydrogen conversion to helium
$D$. $\gamma$-ray emission	$S$. Heavy water
	$T$. Neutrino emission