$Ph-CH_2-CH=CH-CH_3$ $\xrightarrow[(ii) \text{ Alc. KOH}]{(i) \text{ } Br_2}$ ?

An unknown compound $X$ is an unsaturated hydrocarbon. It reacts with $HgSO_4$ and $H_2SO_4$ to give compound $(B)$. Compound $(B)$ on oxidation gives compound $(C)$. Compound $(C)$ on reaction with $NaOH$ and soda lime gives methane. Identify $A$ (which is $X$),$B$,and $C$ by providing the chemical reactions.

By heating a mixture of $CHCl_3$ with silver powder,the compound formed is

$X$ (Symmetrical alkyne) $\xrightarrow{Hg^{2+}/H_3O^{+}}$ $2-$butanone. Which compound reacts with $Ag$ powder to give $X$?

$CH_3-CH_2-CH_2-C \equiv CH \xrightarrow[\text{Excess}]{HCl} ?$

What is the product formed by the hydration of propyne in the presence of $H_2SO_4$ and $HgSO_4$?