<image> Car A and Car B depart simultaneously from points $$A$$ and $$B$$ respectively, traveling towards each other on the same route at constant speeds. Car A stops when it reaches point $$B$$, and Car B stops when it reaches point $$A$$. Car A reaches its destination before Car B.$$.$$ Given that the distance between Car A and Car B is $$y(km)$$ and the travel time of Car B is $$x(h)$$, the function graph of $$y$$ and $$x$$ is shown in the figure.
$$(1)$$ Determine the speed of Car A.
$$(2)$$ Derive the functional relationship between $$y$$ and $$x$$ after Car A reaches point $$B$$.
$$(3)$$ When the distance between the two cars is $$160 km$$ after they meet, find the travel time of Car B.