The reaction of $n$-propyl bromide with ethanolic potassium hydroxide $(KOH)$ produces ...... .

Arrange the following in order of $C-Br$ bond strength in a polar solvent. The structures are as follows:
$(I)$ $1$-methylcyclohexa-$2,4$-dienyl bromide
$(II)$ cyclohexa-$2,4$-dienyl bromide
$(III)$ $1$-methylcyclopenta-$2,4$-dienyl bromide
$(IV)$ cyclopenta-$2,4$-dienyl bromide

Which one of the following is most reactive towards nucleophilic substitution reaction?

The major product $(A)$ formed in the reaction given below is:

Addition of $KI$ accelerates the hydrolysis of primary alkyl halides because

Given below are two statements: one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$.
Assertion $(A)$ : Haloalkanes react with $KCN$ to form alkyl cyanides as a main product while with $AgCN$ they form isocyanide as the main product.
Reason $(R)$ : $KCN$ and $AgCN$ both are highly ionic compounds.
In the light of the above statement,choose the most appropriate answer from the options given below: