Question

Speed of an object can be 0 . HOW???

Answer 1

speed = distance covered per unit time.
Distance is a scalar quantity and does not depend on direction. So suppose an object goes from A to B in 2 seconds and comes back to A in another 2 seconds. So the final distance covered in the 4 seconds is 0 because after 4 seconds it is exactly at that position from where it started.
So speed = 0/4 = 0