The major product of the following reaction is: 
The given reaction involves a dehydrohalogenation process, where a halogen (Br) is eliminated in the presence of an excess base, KOH in ethanol. This reaction typically leads to the formation of alkenes by the elimination of H and Br atoms.
Since the reagent is in excess, it leads to a conjugated diene product.
The elimination occurs in such a way that the resulting product has two double bonds conjugated with the phenyl group.
The correct product formed in this reaction is 6-Phenylhepta-2,4-diene, as it has the conjugation in positions 2 and 4.


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: $g = 10\,\text{m s}^{-2}$) 