Which of the following compounds undergoes aldol condensation?

Identify $X$ and $Y$ in the following reaction:

Identify product $B$ in the following reaction: $\text{Propanone}$ $\xrightarrow{\text{Ba(OH)}_2} A$ $\xrightarrow{\Delta, -\text{H}_2\text{O}} B$

Based on the reaction sequence shown,select the incorrect statement about $P_2$. The reaction starts with cyclohexanone reacting with $Mg-Hg/H_2O$ to form $P_1$,which then reacts with conc. $H_2SO_4$ and heat to form $P_2$.

The reaction of hydrazine $(NH_2NH_2)$ with aldehydes and ketones yields a compound with the general structure:

Among the given pairs,in which pair does the second compound have less enol content than the first compound?