A car is uniformly accelerated on the road, and the displacement within the 3rd second is 6m, and the displacement within the 4th second is 8m. Find (1) The average speed of the car in the two seconds from the beginning of the 3s to the end of the 4th;
6 + 8 = 14 meters
14 meters in 2 seconds = 7 meters/second
which is 0.007 kilometers in (1/3600) hour = 25.2 kilometers/hr