An unsaturated organic compound,$X$ on reaction with hot,acidified $KMnO_4$ gives succinic acid. What is $X$?

Oils are converted into fats by

$CH_2 = CH_2 + B_2H_6 \xrightarrow[H_2O_2]{NaOH} \text{Product}$.
The product in the above reaction is:

Molar mass of the hydrocarbon $(X)$ which on ozonolysis consumes one mole of $O_3$ per mole of $(X)$ and gives one mole each of ethanal and propanone is $...... g\ mol^{-1}$ (Molar mass of $C: 12\ g\ mol^{-1}, H: 1\ g\ mol^{-1}$)

Which of the following alkenes is the most stable?

Which of the following compounds on ozonolysis gives a product that gives a silver mirror with Tollen's reagent?