In the following reaction,$'A'$ is:
$C_2H_5MgBr + CH_2(O)CH_2 \xrightarrow{H_2O} A$

Which of the following reaction sequences would be the best for the synthesis of $t$-butyl alcohol?

Show how will you synthesize:
$(i)$ $1-$phenylethanol from a suitable alkene.
$(ii)$ cyclohexylmethanol using an alkyl halide by an $S_{N}2$ reaction.
$(iii)$ pentan$-1-$ol using a suitable alkyl halide?

Which factor is effective in the preparation of alcohol from alkene using $Al_2O_3$?

In the following sequence of reactions $CH_3CH_2OH$ $\xrightarrow{P + I_2} A$ $\xrightarrow[Ether]{Mg} B$ $\xrightarrow{HCHO} C$ $\xrightarrow{H_2O} D,$ then compound '$D$' is

$2-$methyl$-2-$butene on hydration gives an alcohol $X$. An isomer of $X$ could be prepared from which of the following?