In the figure here, a red car and a green car move toward each other in adjacent lanes and parallel to an x axis. At time t = 0, the red car is at $x_r = 0$ and the green car is at $x_g = 224$ m. If the red car has a constant velocity of 26.0 km/h, the cars pass each other at x = 43.5 m. On the other hand, if the red car has a constant velocity of 52.0 km/h, they pass each other at x = 76.8 m. What are (a) the initial velocity and (b) the (constant) acceleration of the green car? Include the signs.