The radius of a nucleus of a mass number $A$ is directly proportional to

Consider a nucleus ${ }_{30}^{60} X$. Its approximate density is (Take $1 \text{ amu} = 1.6 \times 10^{-27} \text{ kg}$, $R_0 = 1.2 \times 10^{-15} \text{ m}$)

The atomic weight of boron is $10.81$ and it has two isotopes $_5B^{10}$ and $_5B^{11}$. The ratio of $_5B^{10} : _5B^{11}$ in nature is:

$A$ nucleus with atomic mass number $A$ produces another nucleus by losing $2$ alpha particles. The volume of the new nucleus is $60$ times that of the alpha particle. The atomic mass number $A$ of the original nucleus is:

Match the following types of nuclei with their respective examples:

Column-$I$	Column-$II$
$A$. Isotopes	$i$. $Li^7, Be^7$
$B$. Isobars	$ii$. $_8O^{18}, _9F^{19}$
$C$. Isotones	$iii$. $_1H^1, _1H^2$

Ratio of specific charge of $\alpha$-particle to that of proton is