Propane is obtained from propene by which method?

In the following reaction: $CH_3-C(CH_3)_2-CH=CH_2 \xrightarrow{H_2O/H^{+}} A (\text{Major product}) + B (\text{Minor product})$,the major product $A$ is:

Explain the dehalogenation of vicinal dihalides with an example.

Ethylene reacts with $Br_2$ to give $1, 2$-dibromoethane. Which intermediate is formed that leads to anti-addition?

Addition of $Br_2$ to $cis$-$2$-butene would give a product which is

Which of the following reagents is used to test for the unsaturation of an alkene?