Which of the following reagents may be used to distinguish between phenol and benzoic acid ?

Trichloroacetaldehyde was subjected to Cannizzaro’s reaction by using NaOH. The mixture of the products contains sodium trichloroacetate and another compound. The other compound is :

The strongest acid amongst the following compounds is :

Sodium ethoxide has reacted with ethanoyl chloride. The compound that is produced in the above reaction is