5) Suppose a student finds that the total y-component of the outgoing momentum is consistently non-zero. Besides not correctly choosing the x-axis to be parallel to the direction of motion of the incoming puck, what else could be causing this discrepancy

Which of the following situations is impossible? a) an object has velocity directed east and acceleration directed east. b) an object has zero velocity but non-zero acceleration. c) an object has constant non-zero velocity and changing acceleration. d) an object has velocity directed east and acceleration directed west. e) an object has constant non-zero acceleration and changing velocity.