What is the natural source of salicylic acid?

Phenol on heating with zinc dust forms

In the above sequence of reactions,the major products $X$ and $Y$ are

How can picric acid and benzoic acid be distinguished?

Phenol is used as a/an.......?

Consider the following reaction:
The product $'P'$ gives a positive ceric ammonium nitrate test. This is because of the presence of which of these $-OH$ group$(s)$?