Which of the following compounds has the minimum heat of hydrogenation?

In the reaction $Me-C \equiv C-Et$ $\xrightarrow{Na/liq. NH_3} P$ $\xrightarrow[CCl_4]{Br_2} (Q)$; then $Q$ is

The gas evolved by the reaction of ethyl iodide with alcoholic $KOH$,which decolorizes basic $KMnO_4$ solution,is........

What are the products formed in the reaction given below:
$Ph-CH_2-CH=CH-CH_3 \xrightarrow[Zn \text{ dust } + H_2O]{1) O_3} ?$

The reaction of ethene with oxygen in the presence of a silver catalyst gives ....................

$CH_3-CH=CH-CH_3 \xrightarrow[R_2O_2, \Delta]{HBr} \text{ (Anti-Markownikoff's addition)}$
Comment on the optical activity of the products.