



Step 1. Identify Aromatic Stability: The most stable species among the options will be the one that is aromatic as aromatic compounds exhibit additional stability due to delocalized π-electrons.
Step 2. Analyze Each Structure: Option (1): This structure satisfies Huckel’s rule (4n + 2) for aromaticity and has a planar conjugated ring structure, making it aromatic and stable. Other Options: Do not satisfy Huckel’s rule or are non-aromatic.
Step 3. Conclusion: Option (3) is the most stable due to its aromaticity.
Consider the following reaction sequence.

In the given figure, the blocks $A$, $B$ and $C$ weigh $4\,\text{kg}$, $6\,\text{kg}$ and $8\,\text{kg}$ respectively. The coefficient of sliding friction between any two surfaces is $0.5$. The force $\vec{F}$ required to slide the block $C$ with constant speed is ___ N.
(Given: $g = 10\,\text{m s}^{-2}$) 
The equivalent resistance between the points \(A\) and \(B\) in the given circuit is \[ \frac{x}{5}\,\Omega. \] Find the value of \(x\). 