Using Hess's Law, what is Delta H circ for C(graphite) + 2 H 2 (g) -> CH 4 (g) given the enthalpies of combustion of C ( -393.5), H 2 ( -285.8), and CH 4 ( -890.3 kJ/mol)?

Using Hess's Law, what is $Δ H^{\circ}$ for $C(graphite) + 2 H_{2} (g) \to CH_{4} (g)$ given the enthalpies of combustion of C ( $- 393.5$ ), $H_{2}$ ( $- 285.8$ ), and $CH_{4}$ ( $- 890.3 kJ/mol$ )?

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