Given:

$S(s)+O_2(g)S{O}_2(g)$

$2S{O}_3(g)2S{O}_2(g)+O_2(g)$

${}_{r}H=-296\mathrm{.}1kJmo{l}^{-1}$

${}_{r}H=198\mathrm{.}2kJmo{l}^{-1}$

Find ${}_{f}H$ for $S{O}_2(g).$ All substances are in their standard states at STP$.$

A$.-296\mathrm{.}1kJmo{l}^{-1}$

B$.-198\mathrm{.}2kJmo{l}^{-1}$

C$.-790\mathrm{.}4kJmo{l}^{-1}$

D$.296\mathrm{.}1kJmo{l}^{-1}$

E$.790\mathrm{.}4kJmo{l}^{-1}$