Explanation: \(\text{Hints: } \frac{c_1}{c_2} = \sqrt{\frac{T_1}{T_2}}\) \(\text{Solve: } c_2 = c_1 \cdot \sqrt{\frac{T_2}{T_1}} \implies c_2 = 461 \cdot \sqrt{\frac{373}{273}} \implies c_2 = 539 \, \text{m/s}\) \(\text{Ans. (A)}\) \(\text{ব্যাখ্যা: } C_\text{rms} = \sqrt{\frac{3RT}{M}}, \text{ তাই } C_\text{rms} \propto \sqrt{T}, \, \frac{c_1}{c_2} = \sqrt{\frac{T_1}{T_2}}.\)