You can't find the velocity at 15 km/hr. "15 km/hr" is a velocity already!

Here's why:

* Velocity is a measure of speed and direction.

* 15 km/hr tells us the speed (15 kilometers per hour).

* To know the velocity, we also need to know the direction (e.g., 15 km/hr to the east, 15 km/hr north-northwest, etc.).

Example:

* Velocity: A car traveling at 15 km/hr due north.

* Speed: A car traveling at 15 km/hr (no direction specified).

Let me know if you have another question about velocity or speed!