Well, for the distance traveled, the car goes from the northernmost point to the southernmost point. So, it travels half of the circle's circumference = 4.7/2 = 2.35 km.
For the displacement, by going from the northernmost point to the southernmost point, the car basically just travels the diameter of circle.
So, using the formula: Circumference = 2πr = πd
Hence, the d = C/π = 4.7/π = 1.49605... = 1.5 km (2 significant figures)
Therefore, displacement = 1.5 km