The phenomenon in which a proton flips is

An $\alpha$-particle of energy $E$ is liberated during the decay of a nucleus of mass number $236$. The total energy released in this process is

The best neutron moderator is:

If three helium nuclei combine to form a carbon nucleus,then the energy released in this reaction is $\times 10^{-2} \text{ MeV}$. (Given $1 \text{ u} = 931 \text{ MeV}/c^2$,atomic mass of helium $= 4.002603 \text{ u}$,atomic mass of carbon $= 12.000000 \text{ u}$)

Which of the following statements is correct?

When $^{235}_{92}U$ is bombarded with one neutron,fission occurs and the products are three neutrons,$^{94}_{36}Kr$ and: