Among $HCl$,$HBr$,and $HI$,which reactant gives the Kharasch effect (peroxide effect) with an alkene?

Identify the correct statements with respect to $cis/trans$-but$-2$-ene from the following:
$I$. $cis$-but$-2$-ene is more polar than $trans$-but$-2$-ene
$II$. Melting point of $cis$-but$-2$-ene is greater than that of $trans$-but$-2$-ene
$III$. Boiling point of $cis$-but$-2$-ene is greater than that of $trans$-but$-2$-ene
Correct answer is

The product of the following reaction is:

In the given reaction
$CH_3CH_2CH=CHCH_3$ $\xrightarrow{X}$ $CH_3CH_2COOH + CH_3COOH$
The $X$ is

The Diels-Alder reaction will not take place with which of the following reactants?

The number of hydroxyl group$(s)$ in $Q$ is