Answer:
D. Velocity in one dimension may be positive or negative, while speed always has a positive value.
Explanation:
Velocity is the rate at which an object changes position in a specific direction. It has both magnitude and direction.
For example, travelling southeast at 90 km/h is a velocity. It gives both speed and direction.
Velocity is a vector. If your velocity is 90 km/h in one direction, it is -90 km/h in the opposite direction.
Travelling at 90 km/h is a speed. It does not give direction, so it is always positive.
A. Wrong. Velocity has both positive values.
B. Wrong. Speed has only positive values.
C Wrong. Speed has only positive values.