Final answer:
The quantity describing a car passing by at a speed of 36 m/s is velocity, which is speed with a given direction.
Step-by-step explanation:
If someone in a car passes you at a speed of 36 m/s, the quantity that describes their motion is velocity. Velocity refers to the speed of an object in a given direction. Since speed is mentioned along with a reference to the motion of the car passing by, it implies both magnitude and direction, indicating velocity. Acceleration would describe a change in velocity, distance is the scalar quantity of how far an object has moved, and time refers to the duration over which the motion occurs.