Which of the following oil is obtained from benzene after fractional distillation of coal tar?

Conversion of hexane into benzene involves the reaction of:

Amongst the following,the compound that can be most readily sulphonated is

What is the expected order of reactivity of the following compounds in electrophilic chlorination $(Cl_2 + FeCl_3)$? (more reactive $ > $ less reactive)
$I: C_6H_5CH_2CO_2H$
$II: C_6H_5N(CH_3)_2$
$III: C_6H_5OCOCH_3$
$IV: C_6H_5CCl_3$

Ozonolysis of $o$-xylene produces:

Predict the major product of the reaction of $1$-ethyl-$3$-methylbenzene with $KMnO_4$ in an acidic medium under heating.