(130km) / (95km/h) = 1.37h first part of the trip 1.37h x 95 km/h = 130km change 3hr and 20 to 3.34. 3.34h -1.37h = 1.97h 1.97h x 65 km/h = 128km. I hope this will help you out.
The doppler effect is the increase or decrease in the frequency of sound, light, or other waves as the source and observer move toward or away from each other.
