$[21]$ Determine the amount of heat needed to convert $12g$ of substance $x$ from a solid at $8\mathrm{.}0C$ to a gas at $140C,$ given the following parameters.

Melting Point $=20C,$ Boiling Point $=120C$

$H_{\text{f}\text{u}\text{s}}=45k\frac{J}{g},H_{\text{v}\text{a}\text{p}}=180k\frac{J}{g}$

solid