Gasoline has a composition of:

What are $X$ and $Y$ respectively in the following sets of reactions?
$I. \ CH_3CH_2CH_2OH \xrightarrow{PBr_3} X$
$II. \ CH_3CH=CH_2 \xrightarrow{HBr, (C_6H_5COO)_2} Y \text{ (major)}$

Compound $X$ of molecular formula $C_4H_6$ takes up one equivalent of hydrogen in the presence of $Pt$ to form another compound $Y$,which on ozonolysis gives only ethanoic acid. The compound $X$ can be:

Identify $A$ in the following reaction sequence:

Consider the following reaction in which the intermediate carbocation loses $H^{+}$ to give the final product:
Which of the following energy profiles best represents the overall reaction?

Compound $(X)$ will be:
Compound $(X) \xrightarrow[Pt]{5H_2} \text{Saturated compound}$
Compound $(X) \xrightarrow{AgNO_3} \text{Precipitate}$
Compound $(X) \xrightarrow[Me_2S]{O_3} OHC-CH_2-CH_2-CO-CHO + HOOC-CHO + HCOOH + OHC-CHO$