When neutrons are bombarded on the nucleus of $_{92}^{235}U$,the number of emitted neutrons is typically

$A$ ${ }_{92} U^{235}$ nucleus absorbs a neutron and disintegrates into ${ }_{54} X e^{139}$,${ }_{38} S r^{94}$,and $X$. What will be the product $X$?

When two deuteron nuclei fuse to form a helium nucleus,energy is released because the mass of the helium nucleus is .....

Nuclear fission and fusion can be explained on the basis of

$A$ nucleus with mass number $A = 240$ and binding energy per nucleon $= 7.6 \,MeV$ breaks into two fragments each of $A = 120$ with binding energy per nucleon $= 8.5 \,MeV$. Calculate the released energy.

Assertion: Energy is released when heavy nuclei undergo fission or light nuclei undergo fusion.
Reason: For heavy nuclei,binding energy per nucleon increases with increasing $Z$,while for light nuclei,it decreases with increasing $Z$.