Represent the motion in the number line.
Movement to the east is movement to the negative side. Movement to the west is movement to the positive side.
Total displacement = -680m + 430m - 620m = -870m
Total displacement = 860m to the east.
Vi=12m/s Vf=16m/s t=8s a=? a=Vf-Vi/t=16-12/8=4/8=1/2 a=0.5m/s^2
The kinetic energy before equals K after
