Which of the following is formed when propene is heated with bromine at high temperature?

Alkene $R-CH=CH_2$ reacts readily with $B_2H_6$ and the product on oxidation with alkaline hydrogen peroxide produces:

Alcohols can be distinguished from alkenes by

Hardening of oil is done by

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 $C = 12$; $H = 1$; $Br = 80$ ]

Which is the correct order of stability for the given isomers of butene?