Name the alkene with molecular formula $C_{10}H_{20}$.

Reactant $(A)$ in this reaction is

Identify $A$ and $B$ in the following reaction:
Propene $\xrightarrow{\text{HBr (Benzoyl peroxide)}}$ $A$ (Major product)
Propene $\xrightarrow{\text{HI}}$ $B$ (Major product)

How many optical isomers are possible for the compound obtained by the hydrogenation of $(CH_3)_2C = CH-CH_3$?

Which reaction is known as the addition of dihydrogen to an alkene? Explain briefly.

$2,3$-dimethylbut-$2$-ene when reacted with bromine forms a compound which upon heating with alcoholic $KOH$ produces the following major product.