It is impossible for an object to have:constant speed and constant velocityconstant speed and changing velocitychanging speed and constant velocitychanging speed and changing velocity

The statement "It is impossible for an object to have constant speed and changing velocity" is incorrect. Velocity is a vector quantity, meaning it has both magnitude (speed) and direction. An object moving at a constant speed can still have a changing velocity if its direction of motion is changing. For example, an object moving in a circular path at a constant speed has a changing velocity because its direction is constantly changing.

The statement "It is impossible for an object to have changing speed and constant velocity" is correct. If an object's speed is changing, then its velocity (which includes speed in its definition) must also be changing.

The statement "It is impossible for an object to have changing speed and changing velocity" is incorrect. An object can have both a changing speed and a changing velocity. For example, a car accelerating down a straight road is increasing its speed and its velocity is changing because the speed (the magnitude of the velocity) is changing.

The statement "It is impossible for an object to have constant speed and constant velocity" is incorrect. An object moving in a straight line at a constant speed has both a constant speed and a constant velocity, because neither its speed nor its direction is changing.