Final answer:
The odometer measures distance, not displacement, while the speedometer measures speed, not velocity. These instruments provide specific metrics about travel and movement but are not related to determining whether a car is considered used.
Step-by-step explanation:
The student's question relates to motor vehicles and their use status, which can be determined by factors such as mileage, documentation, and vehicle labeling. However, none of the provided reference points directly answer this question. Instead, let's address the given reference points:
- A car's odometer measures the total distance traveled, not displacement. Displacement is a vector quantity that measures the straight-line distance from the starting point to the ending point along with its direction, whereas distance traveled is a scalar quantity that simply measures how far the car has moved, regardless of its starting or end point.
- The speedometer measures speed, not velocity. Speed is the rate at which an object covers distance and is scalar. Velocity is a vector quantity that includes the direction of motion and the speed. Since a speedometer does not provide directional information, it cannot measure velocity.
- For the miles-per-gallon (MPG) ratings, these provide information on fuel efficiency and have a range from 19 to 43 MPG. They are not directly relevant to determining if a motor vehicle is used.