$n$-propyl bromide on treatment with ethanolic potassium hydroxide produces

In the following pairs of halogen compounds,which compound undergoes faster $S_N1$ reaction?
$(i)$ $2$-chloro-$2$-methylpropane and $3$-chloropentane
(ii) $2$-chloroheptane and $1$-chlorohexane

Which of the following substances yields benzoic acid upon oxidation?

Consider the following reaction. Which of the following bases will give the best yield of the alkene $(II)$ as the major product?

The major product of the following reaction is:

The least reactive alkyl chloride in an $S_N2$ reaction is: