Answer
The solution is shown below.
Work Step by Step
In order to determine the reaction mechanism, we must first determine the function of the reagent (1). The second step is to analyze the substrate (2), and lastly but not least we must consider any relevant regiochemical and stereochemical requirements (3).
(1) Reagent in this reaction is NaOH which is both a strong nucleophile and strong base.
(2) For primary substrates, $S_{N}2$ predominates over $E_{}2$.
(3) In $S_{N}2$ mechanism nucleophile attacks at the position where the leaving group is connected and replaces the leaving group with the inversion of configuration. And in $E_{}2$ Zaitsev product is generally favoured over the Hofmann product.
