Ratio of translational degrees of freedom to rotational degrees of freedom of a polyatomic linear gas molecule is

A circular copper ring at $30^{\circ} \mathrm{C}$ has a hole with an area of $9.98 \mathrm{~cm}^2$. It is made to slip onto a steel rod of cross-sectional area of $10 \mathrm{~cm}^2$, by raising the temperature of both ring and rod simultaneously by an amount $\Delta T$. If the coefficient of linear expansion of copper and steel are $17 \times 10^{-6} \rho \mathrm{C}$ and $11 \times 10^{-6} \rho \mathrm{C}$, then minimum value of $\Delta T$ should be

Statement I A device in which heat measurement can be made is called calorimeter.

Statement II Skating is possible on snow due to the formation of water below the skates. Water is formed due to the increase of temperature and ice melts.

Statement III Two bodies at different temperature are mixed in a calorimeter. Total internal energy of the two bodies remains conserved.

Which of the following is correct?

Which of the following statements is not true?