Identify the product $P$ obtained in the following reaction: $C_6H_5OH + HCHO \xrightarrow{\text{Acid}} P$

The following reaction is known as:
$Phenol + HCl + HCN \xrightarrow{Anhyd. ZnCl_2} Salicylaldehyde$

Some compounds and their $pK_a$ values are given. Arrange them in decreasing order of their acidic strength.
$(i)$ Ethanol $(15.9)$,Phenol $(10.0)$,Cresol $(10.1)$,Water $(15.7)$
$(ii)$ $o$-Nitrophenol $(7.2)$,$m$-Nitrophenol $(8.3)$,Ethanol $(15.9)$,Water $(15.7)$,Phenol $(10.0)$

Which of the following is $NOT$ a dihydric alcohol (or dihydric phenol)?

The reaction,
$C_6H_5OH + CHCl_3 \xrightarrow{NaOH/\Delta} \text{o-hydroxybenzaldehyde} + H^+$
is known as:

In the following reaction:
$C_6H_5CH(CH_3)_2 + O_2$ $\xrightarrow{} C_6H_5C(CH_3)_2OOH$ $\xrightarrow{H^+/H_2O} A + B$
The compounds $A$ and $B$ respectively are $......$