Which compound gives lactic acid on hydrolysis after reacting with $HCN$?

Consider the following reaction. The structure of the main product will be

What is the product formed when acetone reacts with $I_2$ in the presence of $NaOH$?

$A$ compound having molecular formula $C_3H_6O$,on reaction with $NH_2NHCONH_2$ produces mainly $P$ (which shows stereoisomerism). $P$ on reaction with $KOH$ / ethylene glycol,$\Delta$ produces propane. Identify $(P)$.

$m$-chlorobenzaldehyde on reaction with conc. $KOH$ at room temperature gives

Grignard reagent is added to .......