$A$ gas formed by the action of alcoholic $KOH$ on ethyl iodide,decolorises alkaline $KMnO_4$ solution. The gas is

The reaction of $HBr$ with the following compound would produce:

Identify $(Z)$ in the above sequence of reactions:
$CH_3-CH_2-CH=CH_2$ $\xrightarrow{HCl/\text{peroxide}} (A)$ $\xrightarrow{EtONa/\Delta} (Z) \text{ (major)}$

In the following reaction,$A$ and $B$ respectively are
$A \xrightarrow{HBr} C_2H_5Br \xrightarrow{B} A$

Which of the following products is not formed during the reaction: $CH_3-CH(CH_3)-CH=CH_2 \xrightarrow{Br_2/aq. NaCl}$?

$CH_3-CH=CH_2 \xrightarrow{HBr} \text{Major product } (A). \text{ } A \text{ is:}$