For the complete combustion of 4 litre ethane, how much oxygen is required ?

For the complete combustion of 4 litres of Co at NTP,the required volume of O_(2) at NTP is :-

For the complete combustion of 4 litres of CO at NTP,the required volume of O_(2) at NTP is :-

In the complete combustion of C_n H_(2n+2) the number of oxygen moles required is :

The volume of oxygen necessary for the complete combustion of 20 litre of propane is :

Find the volume of oxygen at S. T.P. required. for the complete combustion of 2 litres of carbon monoxide at S.T.P.