Reaction of isobutylene with concentrated $H_2SO_4 + SO_3$ (oleum) gives:

What will be the product $B$ formed in the following reaction sequence?
$CH_3CH_2CH_2OH$ $\xrightarrow{PCl_5} A$ $\xrightarrow{alc. KOH} B$

Choose the incorrect option about the following reaction:
$CH_3-CH_2-CH=CH_2 \xrightarrow{HBr, H_2O_2}$

The major product of the following reaction is:

The major product of the following reaction sequence is:

The reaction of an alkene $X$ with bromine produces a compound $Y$,which has $22.22 \% \ C$,$3.71 \% \ H$ and $74.07 \% \ Br$. The ozonolysis of alkene $X$ gives only one product. The alkene $X$ is,
[Given,atomic mass of $C = 12$; $H = 1$; $Br = 80$ ]