In the reaction
$R - C \equiv C - R \xrightarrow{Pd + CaCO_3} B$
$R - C \equiv C - R \xrightarrow{Na + liq. NH_3} A$
$A$ and $B$ are geometrical isomers. Then:

An acyclic hydrocarbon $P$ with molecular formula $C_6H_{10}$ produces acetone as the only organic product through the following reaction sequence,where $Q$ is an intermediate organic compound:
$P (C_6H_{10})$ $\xrightarrow[(ii) NaBH_4/ethanol, (iii) dil. acid]{(i) dil. H_2SO_4/HgSO_4} Q$ $\xrightarrow[(ii) O_3, (iii) Zn/H_2O]{(i) conc. H_2SO_4 (catalytic amount), (-H_2O)} 2 CH_3COCH_3$
$1.$ The structure of compound $P$ is:
$(A)$ $CH_3CH_2CH_2CH_2-C \equiv C-H$
$(B)$ $H_3CH_2C-C \equiv C-CH_2CH_3$
$(C)$ $(CH_3)_2CH-C \equiv C-CH_3$
$(D)$ $(CH_3)_2CH-C \equiv C-H$
$2.$ The structure of compound $Q$ is:
$(A)$ $(CH_3)_2CH-CH(OH)-CH_2CH_3$
$(B)$ $(CH_3)_2CH-CH(OH)-CH_3$
$(C)$ $(CH_3)_2CH-CH_2CH(OH)CH_3$
$(D)$ $CH_3CH_2CH_2CH(OH)CH_2CH_3$
Identify the correct options for $1$ and $2$.

The correct order of acidic nature of the following alkynes is:
$I$. $HC \equiv CH$
$II$. $CH_3-C \equiv C-CH_3$
$III$. $CH_3-C \equiv CH$

$2$-Hexyne reacts with $.......$ to give $trans-2$-hexene.

The number and type of bonds between two carbon atoms in $CaC_2$ are

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