Identify the missing product in the following reaction:
$CH_3CH_2OH \xrightarrow[443 \ K]{H_2SO_4} (?)$

Ethylene possesses:

In the reaction $CH_3CH=CH_2 + H_2O + [O]$ $\xrightarrow{KMnO_4/Acid} CH_3-CH(OH)-CH_2(OH)$ $\xrightarrow{[O]} X + HCOOH$,what is $X$?

$3-$Methylhex$-2-$ene on reaction with $HBr$ in the presence of peroxide forms an addition product $(A)$. The number of possible stereoisomers for '$A$' is $....$.

In the following reaction,$P$ gives two products $Q$ and $R$ each in $40 \,\%$ yield. If the reaction is carried out with $420 \,mg$ of $P$,the reaction yields $108.8 \,mg$ of $Q$. The amount of $R$ produced in the reaction is closest to $....\, mg$.

Provide information about the structure and isomerism of alkenes.