A certain substance has a mass per mole of $50$ g$/$mol$.$ When $339$ J is added as heat to a $29\mathrm{.}0$ g sample, the sample's temperature rises from $22\mathrm{.}0\backslash$deg C to $42\mathrm{.}0\backslash$deg C$.$ What are the $($a$)$ specific heat and $($b$)$ molar specific heat of this substance? $($c$)$ How many moles are present?