一到面试题，题目为：400米的运动场上，甲在乙的前方100米处，甲速度6m/s，乙速度7m/s。甲乙两人每跑到整百米处都要休息5s，问乙何时才能追上甲。-One to face questions, the subject of: 400 meter playground, a B in front of the 100 meters, a speed of 6m/s, B speed 7m/s. B went to the entire two hundred meters of each should rest 5s, asked when we can catch up with a B.