Final answer:
The velocity of the athlete during the first 4 seconds is zero as indicated by the constant position. The velocity of the athlete from t = 4s to t = 7s cannot be determined without more information about the graph or specific position values at those times.
Step-by-step explanation:
The velocity of an athlete during the first 4 seconds can be determined by analyzing the graph of their position versus time. The velocity is equal to the slope of the position-time graph. In this case, the position of the athlete remains constant during the first 4 seconds, indicating that their velocity is zero.
From t = 4s to t = 7s, the velocity can be determined again by analyzing the slope of the position-time graph. If the position-time graph is a straight line, the velocity remains constant. If there is a change in slope, it indicates a change in velocity. Therefore, to determine the velocity from t = 4s to t = 7s, we need more information about the graph or the specific position values at those times.