What is the first step of the addition reaction when $HBr$ is added to propene in the absence of peroxide?

$CH_3 - CH = CH_2 \xrightarrow[(2) CH_3CO_2T]{(1) THF : BD_3} (A)$; Product $(A)$ of the above reaction is

Which of the following is the major product in the following reaction?

$(A) (C_7H_{14}) \xrightarrow[Zn]{O_3} (B) + (C)$
Compound $(A)$ exists as geometrical isomers and $(B)$ gives Cannizzaro reaction. $(A)$ will be:

Identify the major products $X$ and $Y$ in the following reactions:
$(i)$ $C_6H_5-CH=CH_2 + HBr \rightarrow X$
(ii) $C_6H_5-CH_2-CH=CH_2 + HBr \xrightarrow{\text{Peroxide}} Y$

The conversion of $2,3-$dibromobutane to $2-$butene with $Zn$ is