Which of the following does not decolourise bromine solution in carbon disulphide?

Complete the reactions:
$1. CH_4 + O_2 \xrightarrow{Mn_2O_3, \Delta} ?$
$2. CH_3CH_3 + O_2 \xrightarrow{(CH_3COO)_2Mn, \Delta} ?$

$A$ molecule which has $1^{\circ}$,$2^{\circ}$ and $3^{\circ}$ carbon atoms is

Anhydrous sodium acetate on heating with sodalime gives

The decreasing order of boiling points of the following alkanes is:
$(a)$ Heptane
$(b)$ Butane
$(c)$ $2-$methylbutane
$(d)$ $2-$methylpropane
$(e)$ Hexane
Choose the correct answer from the options given below:

Which of the following compounds is $NOT$ formed by the reaction of $CH_4$ with $Cl_2$ in the presence of sunlight?