If the mass defect of ${ }_{5}^{11}B$ is $0.081 \ u$, its average binding energy (in $MeV$) is

Which atomic species cannot be used as a nuclear fuel?

The calculated mass of ${}_{20}Ca^{40}$ is $40.328 \ u$. It releases $306.3 \ MeV$ energy in a nuclear process. Its isotopic mass is

Positron is

The nucleus $^{64}_{29}Cu$ accepts an orbital electron to yield:

Let $m_p$ be the mass of a proton,$m_n$ that of a neutron,$M_1$ that of a $_{10}^{20}Ne$ nucleus,and $M_2$ that of a $_{20}^{40}Ca$ nucleus. Then: