Given below are two statements: one is labelled as Assertion \(A\) and the other as Reason \(R\):
Assertion \(A\): A sound wave has higher speed in solids than in gases.
Reason \(R\): Gases have higher value of Bulk modulus than solids.
Step 1: Evaluate the truth of \(A\) and \(R\). Sound travels faster in solids than in gases due to the higher density and elastic properties of solids, not gases.
Step 2: Determine the correctness of \(R\). In fact, solids generally have a higher Bulk modulus than gases, contradicting the statement of \(R\).
Conclusion: Assertion \(A\) is true, stating that sound waves travel faster in solids is correct, but Reason \(R\) is false as gases typically have a lower Bulk modulus than solids.
A flexible chain of mass $m$ is hanging as shown. Find tension at the lowest point. 

Which one of the following graphs accurately represents the plot of partial pressure of CS₂ vs its mole fraction in a mixture of acetone and CS₂ at constant temperature?

Let \( \alpha = \dfrac{-1 + i\sqrt{3}}{2} \) and \( \beta = \dfrac{-1 - i\sqrt{3}}{2} \), where \( i = \sqrt{-1} \). If
\[ (7 - 7\alpha + 9\beta)^{20} + (9 + 7\alpha - 7\beta)^{20} + (-7 + 9\alpha + 7\beta)^{20} + (14 + 7\alpha + 7\beta)^{20} = m^{10}, \] then the value of \( m \) is ___________.