Accepted Answer
When you know the distance the object covers in one unit of time, you have everything you need to calculate the object's speed.Note that you don't have enough information to say anything about its velocity. You don't know anything about what direction it's traveling, or whether its direction may even be changing. And without direction, you have no velocity, only speed.
Accepted Answer
If you know the distance that an object travels in one unit of time, you can determine the velocity at which it was initially projected.