Which volume of ethane gas, in $\mathrm{cm}^3$, will produce 40  $\mathrm{cm}^3$ of carbon dioxide gas when mixed with 140  $\mathrm{cm}^3$ of oxygen gas, assuming the reaction goes to completion?

Which volume of ethane gas, in $\mathrm{cm}^3$, will produce 40  $\mathrm{cm}^3$ of carbon dioxide gas when mixed with 140  $\mathrm{cm}^3$ of oxygen gas, assuming the reaction goes to completion?

$2C_2H_6( )g+7O_2( g)→4CO_2( g)+6H_2O( g)$