A $40\mathrm{.}0$ kg wagon is towed up a hill inclined at $19\mathrm{.}8\backslash$deg with respect to the horizontal. The tow rope is parallel to the incline and has a tension of $140$ N in it$.$ Assume that the wagon starts from rest at the bottom of the hill, and neglect friction. How fast is the wagon going after moving $79$ m up the hill?

m$/$s