The mass of an $\alpha$-particle is

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A:$ The binding energy per nucleon is practically independent of the atomic number for nuclei of mass number in the range $30$ to $170$.
Reason $R:$ Nuclear force is short-ranged.
In the light of the above statements, choose the correct answer from the options given below:

The average binding energy per nucleon in the nucleus of an atom is approximately

The mass of a $_3^7Li$ nucleus is $0.042 \, u$ less than the sum of the masses of its constituent nucleons. The binding energy per nucleon of the $_3^7Li$ nucleus is approximately ......... $MeV$.

What is the binding energy of ${ }_{14}^{29} Si$ whose atomic mass is $28.976495 u$ (in $MeV$)?
Mass of proton $= 1.007276 u$
Mass of neutron $= 1.008664 u$
(Neglect the electron mass) (Assume $1 u = 931.5 MeV$)

The binding energy per nucleon for ${O^{16}}$ and ${O^{17}}$ are $7.97 \, MeV$ and $7.75 \, MeV$ respectively. How much energy in $MeV$ is required to remove one neutron from ${O^{17}}$?