circular road has a circumference of 2 km. Three people, A, B, and C, start from the same point at the same time, and each travel around for 2 weeks. There are 2 bicycles. B and C start off on bicycles, and A starts on foot. Halfway through, B and C get off and walk, and leave the bicycles for others to ride. It is known that A walks at a speed of 5 kilometers per hour, B and C walk at a speed of 4 kilometers per hour, and all three of them ride bicycles at a speed of 20 kilometers per hour. Please design a way to make 3 people and 2 cars arrive at the end at the same time. So how many minutes does it take to go around for 2 weeks?
一条环形道路，周长为2千米．甲、乙、丙3人从同一点同时出发，每人环行2周．现有自行车2辆，乙和丙骑自行车出发，甲步行出发，中途乙和丙下车步行，把自行车留给其他人骑．已知甲步行的速度是每小时5千米，乙和丙步行的速度是每小时4千米，3人骑车的速度都是每小时20千米．请你设计一种走法，使3个人2辆车同时到达终点．那么环行2周最少要用多少分钟？
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