A plot of binding energy per nucleon $(\frac{E_b}{A})$ versus the mass number $(A)$ shows that nuclei with a small mass number have a small binding energy per nucleon, as the mass number increases the binding energy per nucleon increases, and the value for the binding energy per nucleon has a maximum value for nuclei with a mass number around $60.$ Verify that this is the case by determining the binding energy per nucleon for each of the following four nuclei. $($Let the mass of a proton be $1\mathrm{.}0078$ u $,$ the mass of a neutron be $1\mathrm{.}0087$ u $,$ the mass of ${?}^{2}H$ be $2\mathrm{.}0141$ u $,$ the mass of ${?}^{7}Li$ be $7\mathrm{.}0160$ u $,$ the mass of ${?}^{62}Co$ be $61\mathrm{.}9341$ u $,$ and the mass of ${?}^{109}Ag$ be $108\mathrm{.}9048$ u $.$ Enter your answers in MeV and to at least three significant figures.$)$

$($a$){?}^{2}H$

MeV

$($b$){?}^{7}Li$

MeV

$($c$){?}^{62}Co$

Modify your work from part $($a$)$ to determine the binding energy per nucleon for the nucleus of interest. MeV

$($d$){?}^{109}Ag$

MeV