Answer:
C-D
Explanation:
As you can see from the graph, the distance from A to B was from 0 m to 6 m in a duration of 3 seconds.
Divide 6 meters by 3 seconds to find the speed:
6 ÷ 3 = 2 m/s
B-C is not moving due to a straight line as said in the graph, so speed is
0 m/s.
There is also C-D since the car traveled from a distance of 9 meters
(6 -(-3) = 9) in 3 seconds too. (NOTE: The graph line going down does not mean it is slowing down, but rather going to a certain distance like going backwards)
Divide 9 meters by 3 seconds to get the speed:
9 ÷ 3 = 3 m/s
Between A-B, B-C, and C-D, C-D has the fastest speed recorded with 3 m/s.
A-D does not count here as the line has no connection between point A and point D.
Cheers!