One litre of $CO_2$ is passed over hot cake.The volume becomes 1.4litre.The percent composition of products is

Question

$\begin{array}{1 1}(a)\;0.6\;litre&(b)\;0.8\;litre\;CO_2\\(c)\;0.6\;lCO_2\;and\;0.8\;l\;CO&(d)\;None\;of\;these\end{array}$