What is true for motion in a straight line.

Question

A. if a vechile has zero velocity , it must be stationary.
B.the graph of position against time has to be a straight line.
C.acceleration is the rate of change of speed.
D.velocity is the rate of change of position.
E.a reversing vechile must have negative velocity.
F.two vechiles travelling at the same speed at the same instant of time on the same road must have the same velocity.

Answer 1

B. is false
F. true if they go in the same direction, false if they go in opposite direction
speed does not take into consideration the direction, whereas velocity does.

OK, I give up, what is a vechile ??