What is the amount of energy released by deuterium and tritium fusion (in $,MeV$)?

In a nuclear fission process,a high mass nuclide $(A \approx 236)$ with binding energy $7.6 \ MeV/\text{nucleon}$ dissociates into two middle mass nuclides $(A \approx 118)$,each having a binding energy of $8.6 \ MeV/\text{nucleon}$. The energy released in the process is $MeV$.

$A$ chain reaction is continuous due to

The large-scale destruction that would be caused due to the use of nuclear weapons is called:

The energy released by the fission of one uranium atom is $200 \text{ MeV}$. The number of fissions per second required to produce $6.4 \text{ W}$ power is $\qquad$ .

What is a nuclear chain reaction? Explain the difficulties and their removal for its successful operation.