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

Express unified atomic mass unit $(amu)$ in $kg$.

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$: The nuclear density of nuclides ${ }_{5}^{10} B, { }_{3}^{6} Li, { }_{26}^{56} Fe, { }_{10}^{20} Ne$ and ${ }_{83}^{209} Bi$ can be arranged as $\rho_{ Bi }^{ N } > \rho_{ Fe }^{ N } > \rho_{ Ne }^{ N } > \rho_{ B }^{ N } > \rho_{ Li }^{ N }$.
Reason $R$: The radius $R$ of a nucleus is related to its mass number $A$ as $R = R_0 A^{1/3}$,where $R_0$ is a constant.
In the light of the above statements,choose the correct answer from the options given below:

Which of the following is true for a sample of $U^{235}$ and $U^{238}$ isotopes?

The volume of a nucleus is proportional to ........ (where,$A$ is the mass number of the nucleus).

Find the ratio of the radii of the nuclei $_{13}Al^{27}$ and $_{52}Te^{125}$.