Final answer:
The number 65 m/s East describes the velocity of a person, which is a vector quantity that includes both speed and direction.
Step-by-step explanation:
When a person is going 65 m/s East, the number describes their velocity. Velocity is a vector quantity that combines both the speed of an object (how fast it's moving) and its direction of travel. Unlike speed, which is a scalar quantity that only has magnitude (how fast an object is traveling regardless of its direction), velocity specifies a direction as well. In this case, the direction is East.
Additional examples:
- Average speed is how far something travels over a certain period, like covering 100 kilometers in 2 hours (which would be a speed of 50 km/h).
- Velocity would specify that speed along with a direction, such as 50 km/h North.
Therefore, the correct answer to the question is: C. Velocity.