Select the chain propagation steps in the free-radical chlorination of methane.

 

The number of possible monobromo products is ______________(Excluding stereo isomers)

$\text{Br radical}$ will abstract which of the hydrogens most readily?

Product of the above reaction will be:

Sulphonation is most favourable at the carbon number _______________. 

Arrange the following in decreasing order of reactivity towards EAS (electrophilic aromatic substitution).