Given $C_{(graphite)}+O_2 (g) \to CO_2(g) ; \Delta_r H^{\circ} =-393.5\;kj\;mol^{-1}\\$ $H_2(g)+\large\frac{1}{2}$$O_2(g) \to H_2O(l) ; \Delta_r H^{\circ} =-285.8\;kj\;mol^{-1}\\$
$CO_2(g)+2H_2O(l) \to CH_4(g) +2O_2(g) ; \Delta_{r}H^{\circ} =+890.3\;kJ mol^{-1}\\$ Based on the above thermochemical
equations, the value of $\Delta_r H^{\circ}$ at $298\; K$ for the reaction $ C_{(graphite)}+2H_2(g) \to CH_4(g) $ will be