In an atomic bomb,the energy is released due to

In a nuclear fusion process,a certain mass of hydrogen is converted into helium,resulting in a mass defect of $0.02866 \, u$. The energy released per $1 \, u$ of mass formed is ......... $MeV$. (Given $1 \, u = 931 \, MeV$)

What will be the energy released in joule, in the process of fission by $1 \text{ mg}$ of ${ }_{92}^{240} U$? Assume energy release per fission is $200 \text{ MeV}$. [Use Avogadro's number as $6 \times 10^{23}$ and $1 \text{ eV} = 1.6 \times 10^{-19} \text{ J}$]

Fast neutrons can be easily slowed down by:

During the fission of $_{92}U^{235}$,$0.1\%$ of its mass is converted into energy. How much energy is produced from $1 \, kg$ of $_{92}U^{235}$?

$A$ nuclear reactor provides a power of $300 \, MW$. If the fission of one uranium nucleus ${U^{235}}$ releases $170 \, MeV$ of energy,how many nuclei undergo fission in $1 \, h$?