Hydrofluorocarbons $($HFC$)$ have replaced chlorofluorocarbon gases $($CFC$)$ in refrigerators. What is the molar mass of an HFC if $60\mathrm{.}0$ g occupies a volume of $15\mathrm{.}0$ L at $25\mathrm{.}0$ oC and $1\mathrm{.}00$ atm?