How can i calculate velocity when given time and distance measurements?
i'm trying to get the average velocity of these : i don't necessarily need anyone to do the work, i more so need the formula and a simple demonstration !
distance (m)
average time (s)
0.5
0.5
1.0
2.1
1.5
3.3
2.0
5.5

First of all ... there isn't a shred of information about direction here,
so you're in no position to talk about 'velocity'.  That's not just a
big word for 'speed'.  They're two different things.  So let's just talk
about 'speed'.

Average speed  = 

                 (distance covered in some time)
divided by
                 (time to cover the distance).

You're given a distance and a time ?  Great !  Divide the distance
by the time, and you have the average speed during that time.

And don't forget about the units.

(0.5 meter) in (1.5 seconds) ?

Average speed = (0.5 meter) / (1.5 seconds)  =  1/3 meter/second .
.
.
etc.

Is a  vector quantity  that refers to "the rate at which an object changes its position." imagine a person moving rapidly - one step forward and one step back - always returning to the original starting position. while this might result in a frenzy of activity, it would result in a zero velocity. because the person always returns to the original position, the motion would never result in a change in position. since velocity is defined as the rate at which the position changes, this motion results in zero velocity. if a person in motion wishes to maximize their velocity, then that person must make every effort to maximize the amount that they are displaced from their original position. every step must go into moving that person further from where he or she started. for certain, the person should never change directions and begin to return to the starting position.