which of the following below is a velocity? 12 m/s 12 cm/day 12 mi/hr none are correct 12 km/h

Explanation:

Step1: Recall velocity definition

Velocity is a vector quantity that has both magnitude and direction. Here we are just looking at the magnitude - speed units. Standard units of velocity (speed) are distance per time. But we also need to consider the context of typical velocities.

Step2: Analyze each option

12 m/s is a common unit for speed/velocity in physics for moderate - speed objects like running humans etc. 12 cm/day is an extremely slow rate, not a typical velocity for most common physical scenarios. 12 km/h is also a common unit for velocities like walking or slow - moving vehicles. 12 m/h is a very slow speed. However, velocity requires a direction to be fully defined. Since none of these options have a direction given, strictly speaking, they are speeds. But if we consider just the magnitude part in the context of velocity units, all of the first four options are valid speed (magnitude of velocity) units. But if we assume the question is asking for a "complete" velocity (magnitude + direction) and since none have direction, the answer "None are correct" is valid.

Answer:

None are correct