一队特种兵,排成一个50米方队,以不变的速度向前行进。他们的一只警犬从后排的中心(图中所示的A点)向前排的中心(图中所示的B点)沿直线小跑,到达B点后沿原来的路线返回,当警犬回到A点时,特种兵方队正好行进了50米。假设警犬小跑 A team of special forces, arranged in a 50 m square team, at a constant pace of progress. One of their dogs hurried in a straight line from the center of the rear row (point A in the figure) to the center in the front row (point B shown in the figure), returned along the original route after reaching point B, At point A, the Special Forces team traveled just 50 meters. Suppose the police dog trot