For the sequence of reactions $A$ $\xrightarrow{C_2H_5MgI} B$ $\xrightarrow{H_2O / H^{+}} \text{tert-pentyl alcohol}$. The compound $A$ in the sequence is

Reaction of ethyl formate with excess of $CH_3MgI$ followed by hydrolysis gives

Reaction of iso-propylbenzene with $O_2$ followed by treatment with $H_3O^{+}$ forms phenol and a by-product $P$. Reaction of $P$ with $3$ equivalents of $Cl_2$ gives compound $Q$. Treatment of $Q$ with $Ca(OH)_2$ produces compound $R$ and calcium salt $S$. The correct statement(s) regarding $P, Q, R$ and $S$ is(are):
$(A)$ Reaction of $P$ with $R$ in the presence of $KOH$ gives chloritone.
$(B)$ Reaction of $R$ with $O_2$ in the presence of light gives phosgene gas.
$(C)$ $Q$ reacts with aqueous $NaOH$ to produce $Cl_3CCH_2OH$ and $Cl_3CCOONa$.
$(D)$ $S$ on heating gives $P$.

The reaction in which $NaCN/C_2H_5OH/HOH$ is used is:

How will you convert butan-$2$-one to propanoic acid?
$CH_3-CH_2-CO-CH_3 + I_2 + NaOH$ $\rightarrow C_2H_5CO_2^-Na^+ + CHI_3$ $\xrightarrow{H^+} C_2H_5COOH$

The image shows the hydration equilibrium of formaldehyde and acetone. Identify the values of $x$ and $y$ representing the percentage of hydrate formed at equilibrium for formaldehyde and acetone,respectively.