This is a writing exercise for the student, and answers will vary. Here is a sample. Astra continually drives around a square track at constant speed. During what time intervals is her velocity constant? a. The entire time b. Only while she is moving along one of the 4 straight sides c. Only when she is turning a corner d. There is no time interval during which her velocity is constant The correct choice is B. Velocity is constant when an object moves at constant speed, and in a straight line.