Which physiographic division of India is known for its alluvial plains?

Match the physical quantities with their correct $\mathrm{SI}$ units.

The correct match is

The pressure (P) and density $\left(\rho \right)$ of a diatomic gas $\left(\gamma =\frac{7}{5}\right)$ changes from $P_1 ,{\rho }_1$ to $P_2,{\rho }_2$ . What is the value of $\frac{P_1}{P_2}$ if $\frac{{\rho }_1}{{\rho }_2}=32 ?$

One mole of an ideal gas at $300 \mathrm{K}$ is expanded isothermally from an initial volume of $1$ litre to $10$ litre. $∆\mathrm{U}$ for this process is: 

$\left(\mathrm{R}=2\mathrm{ }\mathrm{cal}\mathrm{ }{\mathrm{mol}}^{-1}\mathrm{ }{\mathrm{K}}^{-1}\right)$