Major product of the given reaction is $CH_2=CH-CH_2-I \xrightarrow[CCl_4]{HI(excess)}$

In the reaction,$H_2C = CH_2 \xrightarrow{\text{cold alkaline } KMnO_4} (A)$. Product $A$ is :

Predict the major product $A$ for the following reaction:
$2\text{-methylbuta-1,3-diene} + HBr (1 \text{ eq.}) \xrightarrow{-80^{\circ}C (1,2\text{-addition})} A$

The major product $(P)$ formed in the reaction below is: $HC \equiv C-CH_2-CH=CH_2 \xrightarrow[CCl_4, 253 \ K]{Br_2(1 \ mol)} P$

Write the main product of the given reactions:
$1$. $CH_3-CH=CH-CH_3 \xrightarrow[cold, Na_2CO_3]{KMnO_4}$
$2$. $2,3-$Dimethylbut$-2-$ene $\xrightarrow{Baeyer\ test}$

$A$ hydrocarbon reacts with hypochlorous acid to give $1-$chloro$-2-$hydroxyethane. The hydrocarbon is